<?xml version="1.0" encoding="us-ascii" standalone="yes"?>
<!--XBRL Document Created with XBRLMaster-->
<!--Version: 2.3.08-->
<!--Based on XBRL 2.1-->
<!--Date of creation: 10/21/2026-->
<!--Software architectural design and coding: A'c Dharmapremananda Avt.-->
<!--Copyright (c) 2026 I-NET Business Solutions, Inc. All Rights Reserved.-->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://karx.com/role/Cover" xlink:href="karx-20260831.xsd#Cover" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CondensedConsolidatedBalanceSheets" xlink:href="karx-20260831.xsd#CondensedConsolidatedBalanceSheets" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:href="karx-20260831.xsd#CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CondensedConsolidatedStatementsOfOperationsAndComprehensiveLossUnaudited" xlink:href="karx-20260831.xsd#CondensedConsolidatedStatementsOfOperationsAndComprehensiveLossUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CondensedConsolidatedStatementsOfChangesInShareholdersEquityDeficitUnaudited" xlink:href="karx-20260831.xsd#CondensedConsolidatedStatementsOfChangesInShareholdersEquityDeficitUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CondensedConsolidatedStatementsOfCashFlowUnaudited" xlink:href="karx-20260831.xsd#CondensedConsolidatedStatementsOfCashFlowUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#InsiderTradingArrangements" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPolicies" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/PrepaidExpenses" xlink:href="karx-20260831.xsd#PrepaidExpenses" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/Inventory" xlink:href="karx-20260831.xsd#Inventory" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/PropertyAndEquipment" xlink:href="karx-20260831.xsd#PropertyAndEquipment" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/AcquiredProjectPipeline" xlink:href="karx-20260831.xsd#AcquiredProjectPipeline" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ContractFulfillmentAssets" xlink:href="karx-20260831.xsd#ContractFulfillmentAssets" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomer" xlink:href="karx-20260831.xsd#OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomer" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LoanReceivable" xlink:href="karx-20260831.xsd#LoanReceivable" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/DeferredRevenue" xlink:href="karx-20260831.xsd#DeferredRevenue" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherCurrentLiabilities" xlink:href="karx-20260831.xsd#OtherCurrentLiabilities" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ConvertibleNotes" xlink:href="karx-20260831.xsd#ConvertibleNotes" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LongTermDebt" xlink:href="karx-20260831.xsd#LongTermDebt" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoan" xlink:href="karx-20260831.xsd#ReceivablesFinancingObligationsAndTermLoan" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ShareholdersEquity" xlink:href="karx-20260831.xsd#ShareholdersEquity" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/Warrants" xlink:href="karx-20260831.xsd#Warrants" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InvestmentsAndSecuritiesReceivable" xlink:href="karx-20260831.xsd#InvestmentsAndSecuritiesReceivable" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InternallyDevelopedSoftware" xlink:href="karx-20260831.xsd#InternallyDevelopedSoftware" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/StockOptionPlan" xlink:href="karx-20260831.xsd#StockOptionPlan" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/IncomeTaxes" xlink:href="karx-20260831.xsd#IncomeTaxes" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LossPerShare" xlink:href="karx-20260831.xsd#LossPerShare" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/RelatedPartyTransactions" xlink:href="karx-20260831.xsd#RelatedPartyTransactions" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/Concentrations" xlink:href="karx-20260831.xsd#Concentrations" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CommitmentsAndContingencies" xlink:href="karx-20260831.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/SubsequentEvents" xlink:href="karx-20260831.xsd#SubsequentEvents" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesPolicies" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesTables" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/PrepaidExpensesTables" xlink:href="karx-20260831.xsd#PrepaidExpensesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InventoryTables" xlink:href="karx-20260831.xsd#InventoryTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/PropertyAndEquipmentTables" xlink:href="karx-20260831.xsd#PropertyAndEquipmentTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/AcquiredProjectPipelineTables" xlink:href="karx-20260831.xsd#AcquiredProjectPipelineTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ContractFulfillmentAssetsTables" xlink:href="karx-20260831.xsd#ContractFulfillmentAssetsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerTables" xlink:href="karx-20260831.xsd#OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/DeferredRevenueTables" xlink:href="karx-20260831.xsd#DeferredRevenueTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherCurrentLiabilitiesTables" xlink:href="karx-20260831.xsd#OtherCurrentLiabilitiesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ConvertibleNotesTables" xlink:href="karx-20260831.xsd#ConvertibleNotesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LongTermDebtTables" xlink:href="karx-20260831.xsd#LongTermDebtTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoanTables" xlink:href="karx-20260831.xsd#ReceivablesFinancingObligationsAndTermLoanTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/WarrantsTables" xlink:href="karx-20260831.xsd#WarrantsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InvestmentsAndSecuritiesReceivableTables" xlink:href="karx-20260831.xsd#InvestmentsAndSecuritiesReceivableTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/StockOptionPlanTables" xlink:href="karx-20260831.xsd#StockOptionPlanTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LossPerShareTables" xlink:href="karx-20260831.xsd#LossPerShareTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CommitmentsAndContingenciesTables" xlink:href="karx-20260831.xsd#CommitmentsAndContingenciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPoliciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails1" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPoliciesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails2" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPoliciesDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails3" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPoliciesDetails3" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetailsNarrative" xlink:href="karx-20260831.xsd#BasisOfPresentationAndSignificantAccountingPoliciesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/PrepaidExpensesDetails" xlink:href="karx-20260831.xsd#PrepaidExpensesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InventoryDetails" xlink:href="karx-20260831.xsd#InventoryDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/PropertyAndEquipmentDetails" xlink:href="karx-20260831.xsd#PropertyAndEquipmentDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/PropertyAndEquipmentDetailsNarrative" xlink:href="karx-20260831.xsd#PropertyAndEquipmentDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/AcquiredProjectPipelineDetails" xlink:href="karx-20260831.xsd#AcquiredProjectPipelineDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/AcquiredProjectPipelineDetailsNarrative" xlink:href="karx-20260831.xsd#AcquiredProjectPipelineDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ContractFulfillmentAssetsDetails" xlink:href="karx-20260831.xsd#ContractFulfillmentAssetsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerDetails" xlink:href="karx-20260831.xsd#OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerDetailNarrative" xlink:href="karx-20260831.xsd#OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerDetailNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LoanReceivableDetailNarrative" xlink:href="karx-20260831.xsd#LoanReceivableDetailNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/DeferredRevenueDetails" xlink:href="karx-20260831.xsd#DeferredRevenueDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/DeferredRevenueDetailsNarrative" xlink:href="karx-20260831.xsd#DeferredRevenueDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherCurrentLiabilitiesDetails" xlink:href="karx-20260831.xsd#OtherCurrentLiabilitiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/OtherCurrentLiabilitiesDetailsNarrative" xlink:href="karx-20260831.xsd#OtherCurrentLiabilitiesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ConvertibleNotesDetails" xlink:href="karx-20260831.xsd#ConvertibleNotesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ConvertibleNotesDetailsNarrative" xlink:href="karx-20260831.xsd#ConvertibleNotesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LongTermDebtDetails" xlink:href="karx-20260831.xsd#LongTermDebtDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LongTermDebtDetailsNarrative" xlink:href="karx-20260831.xsd#LongTermDebtDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoanDetails" xlink:href="karx-20260831.xsd#ReceivablesFinancingObligationsAndTermLoanDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoanDetailsNarrative" xlink:href="karx-20260831.xsd#ReceivablesFinancingObligationsAndTermLoanDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ShareholdersEquityDetailNarrative" xlink:href="karx-20260831.xsd#ShareholdersEquityDetailNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/WarrantsDetails" xlink:href="karx-20260831.xsd#WarrantsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/WarrantsDetailsNarrative" xlink:href="karx-20260831.xsd#WarrantsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InvestmentsAndSecuritiesReceivableDetails" xlink:href="karx-20260831.xsd#InvestmentsAndSecuritiesReceivableDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InvestmentsAndSecuritiesReceivableDetailsNarrative" xlink:href="karx-20260831.xsd#InvestmentsAndSecuritiesReceivableDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/InternallyDevelopedSoftwareDetailsNarrative" xlink:href="karx-20260831.xsd#InternallyDevelopedSoftwareDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/StockOptionPlanDetails" xlink:href="karx-20260831.xsd#StockOptionPlanDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/StockOptionPlanDetailNarrative" xlink:href="karx-20260831.xsd#StockOptionPlanDetailNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/IncomeTaxesDetailNarrative" xlink:href="karx-20260831.xsd#IncomeTaxesDetailNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LossPerShareDetails" xlink:href="karx-20260831.xsd#LossPerShareDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/LossPerShareDetailsNarrative" xlink:href="karx-20260831.xsd#LossPerShareDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/RelatedPartyTransactionsDetailsNarrative" xlink:href="karx-20260831.xsd#RelatedPartyTransactionsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/ConcentrationsDetailsNarrative" xlink:href="karx-20260831.xsd#ConcentrationsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CommitmentsAndContingenciesDetails" xlink:href="karx-20260831.xsd#CommitmentsAndContingenciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:href="karx-20260831.xsd#CommitmentsAndContingenciesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://karx.com/role/SubsequentEventsDetailsNarrative" xlink:href="karx-20260831.xsd#SubsequentEventsDetailsNarrative" xlink:type="simple" />
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/Cover" xlink:title="00000001 - Document - Cover Page Information">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CoverAbstract" xlink:label="loc_deiCoverAbstract" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityRegistrantName" xlink:label="loc_deiEntityRegistrantName" />
    <link:presentationArc order="0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityRegistrantName" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCentralIndexKey" xlink:label="loc_deiEntityCentralIndexKey" />
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityCentralIndexKey" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentType" xlink:label="loc_deiDocumentType" />
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiDocumentType" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentFlag" xlink:label="loc_deiAmendmentFlag" />
    <link:presentationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiAmendmentFlag" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CurrentFiscalYearEndDate" xlink:label="loc_deiCurrentFiscalYearEndDate" />
    <link:presentationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiCurrentFiscalYearEndDate" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntitySmallBusiness" xlink:label="loc_deiEntitySmallBusiness" />
    <link:presentationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntitySmallBusiness" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityShellCompany" xlink:label="loc_deiEntityShellCompany" />
    <link:presentationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityShellCompany" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany" xlink:label="loc_deiEntityEmergingGrowthCompany" />
    <link:presentationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityEmergingGrowthCompany" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCurrentReportingStatus" xlink:label="loc_deiEntityCurrentReportingStatus" />
    <link:presentationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityCurrentReportingStatus" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_deiDocumentPeriodEndDate" />
    <link:presentationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiDocumentPeriodEndDate" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFilerCategory" xlink:label="loc_deiEntityFilerCategory" />
    <link:presentationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityFilerCategory" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="loc_deiDocumentFiscalPeriodFocus" />
    <link:presentationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiDocumentFiscalPeriodFocus" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentFiscalYearFocus" xlink:label="loc_deiDocumentFiscalYearFocus" />
    <link:presentationArc order="12" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiDocumentFiscalYearFocus" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityExTransitionPeriod" xlink:label="loc_deiEntityExTransitionPeriod" />
    <link:presentationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityExTransitionPeriod" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="loc_deiEntityCommonStockSharesOutstanding" />
    <link:presentationArc order="14" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityCommonStockSharesOutstanding" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentQuarterlyReport" xlink:label="loc_deiDocumentQuarterlyReport" />
    <link:presentationArc order="15" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiDocumentQuarterlyReport" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentTransitionReport" xlink:label="loc_deiDocumentTransitionReport" />
    <link:presentationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiDocumentTransitionReport" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFileNumber" xlink:label="loc_deiEntityFileNumber" />
    <link:presentationArc order="17" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityFileNumber" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationStateCountryCode" xlink:label="loc_deiEntityIncorporationStateCountryCode" />
    <link:presentationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityIncorporationStateCountryCode" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityTaxIdentificationNumber" xlink:label="loc_deiEntityTaxIdentificationNumber" />
    <link:presentationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityTaxIdentificationNumber" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine1" xlink:label="loc_deiEntityAddressAddressLine1" />
    <link:presentationArc order="20" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityAddressAddressLine1" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine2" xlink:label="loc_deiEntityAddressAddressLine2" />
    <link:presentationArc order="21" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityAddressAddressLine2" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCityOrTown" xlink:label="loc_deiEntityAddressCityOrTown" />
    <link:presentationArc order="22" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityAddressCityOrTown" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressStateOrProvince" xlink:label="loc_deiEntityAddressStateOrProvince" />
    <link:presentationArc order="23" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityAddressStateOrProvince" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressPostalZipCode" xlink:label="loc_deiEntityAddressPostalZipCode" />
    <link:presentationArc order="24" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityAddressPostalZipCode" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode" xlink:label="loc_deiCityAreaCode" />
    <link:presentationArc order="25" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiCityAreaCode" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber" xlink:label="loc_deiLocalPhoneNumber" />
    <link:presentationArc order="26" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiLocalPhoneNumber" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityInteractiveDataCurrent" xlink:label="loc_deiEntityInteractiveDataCurrent" />
    <link:presentationArc order="27" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiEntityInteractiveDataCurrent" xlink:type="arc" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentDescription" xlink:label="loc_deiAmendmentDescription" />
    <link:presentationArc order="28" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_deiCoverAbstract" xlink:to="loc_deiAmendmentDescription" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CondensedConsolidatedBalanceSheets" xlink:title="110200 - Statement - Condensed Consolidated Balance Sheets">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaapAssetsAbstract_05da06" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapAssetsAbstract_05da06" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaapAssetsCurrentAbstract_76b8bd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapAssetsCurrentAbstract_76b8bd" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_653c27" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_653c27" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent_d808e3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapAccountsReceivableNetCurrent_d808e3" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet_8d3f73" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapInventoryNet_8d3f73" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="loc_us-gaapReceivablesNetCurrent_04f0b7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapReceivablesNetCurrent_04f0b7" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NotesReceivableNet" xlink:label="loc_us-gaapNotesReceivableNet_d6336e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapNotesReceivableNet_d6336e" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="loc_us-gaapPrepaidExpenseCurrent_5de524" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapPrepaidExpenseCurrent_5de524" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityMethodInvestments" xlink:label="loc_us-gaapEquityMethodInvestments_89ed07" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapEquityMethodInvestments_89ed07" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherReceivablesNetCurrent" xlink:label="loc_us-gaapOtherReceivablesNetCurrent_61cc36" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapOtherReceivablesNetCurrent_61cc36" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsCurrent" xlink:label="loc_us-gaapOtherAssetsCurrent_507b35" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapOtherAssetsCurrent_507b35" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaapAssetsCurrent_bd6878" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapAssetsCurrent_bd6878" order="12" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet_b09be8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet_b09be8" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaapOperatingLeaseRightOfUseAsset_e28096" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapOperatingLeaseRightOfUseAsset_e28096" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNet" xlink:label="loc_us-gaapContractWithCustomerAssetNet_a6ba66" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapContractWithCustomerAssetNet_a6ba66" order="15" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaapOtherAssetsNoncurrent_dd095e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapOtherAssetsNoncurrent_dd095e" order="16" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedComputerSoftwareNet" xlink:label="loc_us-gaapCapitalizedComputerSoftwareNet_3a811f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapCapitalizedComputerSoftwareNet_3a811f" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsNet_a7c760" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsNet_a7c760" order="18" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets_21ed5d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapAssets_21ed5d" order="19" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_4e4b06" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_4e4b06" order="20" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaapLiabilitiesCurrentAbstract_6ceba2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapLiabilitiesCurrentAbstract_6ceba2" order="21" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent_3ba823" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_6ceba2" xlink:to="loc_us-gaapAccountsPayableCurrent_3ba823" order="22" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaapDeferredRevenueCurrent_1031ec" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_6ceba2" xlink:to="loc_us-gaapDeferredRevenueCurrent_1031ec" order="23" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableCurrent" xlink:label="loc_us-gaapConvertibleNotesPayableCurrent_abb88d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_6ceba2" xlink:to="loc_us-gaapConvertibleNotesPayableCurrent_abb88d" order="24" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPayableCurrent" xlink:label="loc_us-gaapInterestPayableCurrent_75ff97" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_6ceba2" xlink:to="loc_us-gaapInterestPayableCurrent_75ff97" order="25" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilitiesCurrent" xlink:label="loc_us-gaapDerivativeLiabilitiesCurrent_ebac41" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_6ceba2" xlink:to="loc_us-gaapDerivativeLiabilitiesCurrent_ebac41" order="26" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityCurrent_2f8dc5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapOperatingLeaseLiabilityCurrent_2f8dc5" order="27" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancingReceivableDeferredIncome" xlink:label="loc_us-gaapFinancingReceivableDeferredIncome_ff2eae" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapFinancingReceivableDeferredIncome_ff2eae" order="28" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermLoansPayable" xlink:label="loc_us-gaapLongTermLoansPayable_dae774" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapLongTermLoansPayable_dae774" order="29" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaapOtherLiabilitiesCurrent_0fbf0d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapOtherLiabilitiesCurrent_0fbf0d" order="30" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaapLiabilitiesCurrent_e279ec" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapLiabilitiesCurrent_e279ec" order="31" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaapLongTermDebt_4be9b5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapLongTermDebt_4be9b5" order="32" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityNoncurrent_0fdde3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapOperatingLeaseLiabilityNoncurrent_0fdde3" order="33" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleLongTermNotesPayable" xlink:label="loc_us-gaapConvertibleLongTermNotesPayable_82e47f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapConvertibleLongTermNotesPayable_82e47f" order="34" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities_e0a416" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapLiabilities_e0a416" order="35" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaapCommitmentsAndContingencies_cc9ff8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapCommitmentsAndContingencies_cc9ff8" order="36" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaapStockholdersEquityAbstract_9cbff4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapStockholdersEquityAbstract_9cbff4" order="37" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue_f1bc92" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_9cbff4" xlink:to="loc_us-gaapCommonStockValue_f1bc92" order="38" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaapAdditionalPaidInCapital_a4687a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_9cbff4" xlink:to="loc_us-gaapAdditionalPaidInCapital_a4687a" order="39" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit_fcce8b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_9cbff4" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit_fcce8b" order="40" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax_08f659" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_9cbff4" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax_08f659" order="41" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity_feaf1e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_9cbff4" xlink:to="loc_us-gaapStockholdersEquity_feaf1e" order="42" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity_480c09" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_db9e35" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquity_480c09" order="43" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:title="110201 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaapStatementOfFinancialPositionAbstract_4def4b" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllowanceForNotesAndLoansReceivableCurrent" xlink:label="loc_us-gaapAllowanceForNotesAndLoansReceivableCurrent_5f16a6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_4def4b" xlink:to="loc_us-gaapAllowanceForNotesAndLoansReceivableCurrent_5f16a6" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaapStockholdersEquityAbstract_8d7a92" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfFinancialPositionAbstract_4def4b" xlink:to="loc_us-gaapStockholdersEquityAbstract_8d7a92" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaapCommonStockParOrStatedValuePerShare_4cb393" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_8d7a92" xlink:to="loc_us-gaapCommonStockParOrStatedValuePerShare_4cb393" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaapCommonStockSharesAuthorized_d53aeb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_8d7a92" xlink:to="loc_us-gaapCommonStockSharesAuthorized_d53aeb" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued_6fb01e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_8d7a92" xlink:to="loc_us-gaapCommonStockSharesIssued_6fb01e" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding_393adc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStockholdersEquityAbstract_8d7a92" xlink:to="loc_us-gaapCommonStockSharesOutstanding_393adc" order="6" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CondensedConsolidatedStatementsOfOperationsAndComprehensiveLossUnaudited" xlink:title="124100 - Statement - Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementAbstract" xlink:label="loc_us-gaapIncomeStatementAbstract_a84974" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OperationsAbstract" xlink:label="loc_karxOperationsAbstract_b3ec6c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_karxOperationsAbstract_b3ec6c" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues_b13438" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOperationsAbstract_b3ec6c" xlink:to="loc_us-gaapRevenues_b13438" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaapCostOfRevenue_3c8edb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOperationsAbstract_b3ec6c" xlink:to="loc_us-gaapCostOfRevenue_3c8edb" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaapGrossProfit_05be7c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOperationsAbstract_b3ec6c" xlink:to="loc_us-gaapGrossProfit_05be7c" order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketingExpense" xlink:label="loc_us-gaapMarketingExpense_effdb7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOperationsAbstract_b3ec6c" xlink:to="loc_us-gaapMarketingExpense_effdb7" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalariesAndWages" xlink:label="loc_us-gaapSalariesAndWages_26169a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapSalariesAndWages_26169a" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProfessionalFees" xlink:label="loc_us-gaapProfessionalFees_2a6182" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapProfessionalFees_2a6182" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="loc_us-gaapProvisionForDoubtfulAccounts_4bdb37" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapProvisionForDoubtfulAccounts_4bdb37" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCostAndExpenseOperating" xlink:label="loc_us-gaapOtherCostAndExpenseOperating_6cc134" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapOtherCostAndExpenseOperating_6cc134" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaapOperatingExpenses_af4fa1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapOperatingExpenses_af4fa1" order="10" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaapOperatingIncomeLoss_0ceaf1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapOperatingIncomeLoss_0ceaf1" order="11" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeExpenseNet" xlink:label="loc_us-gaapInterestIncomeExpenseNet_0f666b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapInterestIncomeExpenseNet_0f666b" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnInvestments" xlink:label="loc_us-gaapGainLossOnInvestments_0a9ebb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapGainLossOnInvestments_0a9ebb" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeGainLossOnDerivativeNet" xlink:label="loc_us-gaapDerivativeGainLossOnDerivativeNet_64a432" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapDerivativeGainLossOnDerivativeNet_64a432" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaapOtherNonoperatingIncomeExpense_86e3da" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapOtherNonoperatingIncomeExpense_86e3da" order="15" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_7eeb61" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_7eeb61" order="16" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaapIncomeTaxExpenseBenefit_e8bacb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapIncomeTaxExpenseBenefit_e8bacb" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss_df6912" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapNetIncomeLoss_df6912" order="18" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_3c0d20" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_3c0d20" order="19" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaapComprehensiveIncomeNetOfTax_ca03a4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapComprehensiveIncomeNetOfTax_ca03a4" order="20" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaapEarningsPerShareAbstract_c45a7c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapEarningsPerShareAbstract_c45a7c" order="21" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaapWeightedAverageNumberOfDilutedSharesOutstanding_1d9d8b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapWeightedAverageNumberOfDilutedSharesOutstanding_1d9d8b" order="22" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaapEarningsPerShareDiluted_956ade" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncomeStatementAbstract_a84974" xlink:to="loc_us-gaapEarningsPerShareDiluted_956ade" order="23" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CondensedConsolidatedStatementsOfChangesInShareholdersEquityDeficitUnaudited" xlink:title="148600 - Statement - Condensed Consolidated Statements of Changes in Shareholders Equity (Deficit) (Unaudited)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="loc_us-gaapStatementOfStockholdersEquityAbstract_f838c8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_59e4df" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfStockholdersEquityAbstract_f838c8" xlink:to="loc_us-gaapStatementTable_59e4df" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_5762e7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_59e4df" xlink:to="loc_us-gaapStatementLineItems_5762e7" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaapStatementEquityComponentsAxis_91b71f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_59e4df" xlink:to="loc_us-gaapStatementEquityComponentsAxis_91b71f" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain_5aa757" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementEquityComponentsAxis_91b71f" xlink:to="loc_us-gaapEquityComponentDomain_5aa757" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember_9c50e4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEquityComponentDomain_5aa757" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember_9c50e4" order="1021" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaapCommonStockMember_7dcadc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEquityComponentDomain_5aa757" xlink:to="loc_us-gaapCommonStockMember_7dcadc" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaapAdditionalPaidInCapitalMember_bb87a5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEquityComponentDomain_5aa757" xlink:to="loc_us-gaapAdditionalPaidInCapitalMember_bb87a5" order="1023" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaapRetainedEarningsMember_306639" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEquityComponentDomain_5aa757" xlink:to="loc_us-gaapRetainedEarningsMember_306639" order="1024" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaapSharesIssued_71794c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapSharesIssued_71794c" order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity_0b5660" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockholdersEquity_0b5660" order="2" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesShareBasedCompensation_4c35c9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesShareBasedCompensation_4c35c9" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueShareBasedCompensation_61178f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueShareBasedCompensation_61178f" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_2a516e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_2a516e" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueConversionOfConvertibleSecurities_7bdef5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueConversionOfConvertibleSecurities_7bdef5" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationAndExerciseOfStockOptions" xlink:label="loc_us-gaapAdjustmentsToAdditionalPaidInCapitalSharebasedCompensationAndExerciseOfStockOptions_1de7ec" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapAdjustmentsToAdditionalPaidInCapitalSharebasedCompensationAndExerciseOfStockOptions_1de7ec" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss_6d1bc3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapNetIncomeLoss_6d1bc3" order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25b219" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25b219" order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues_159709" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues_159709" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueNewIssues_785df1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueNewIssues_785df1" order="11" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockIssuedDuringPeriodSharesCommitmentSharesIssued" xlink:label="loc_karxStockIssuedDuringPeriodSharesCommitmentSharesIssued_24912a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_karxStockIssuedDuringPeriodSharesCommitmentSharesIssued_24912a" order="12" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockIssuedDuringPeriodValueCommitmentSharesIssued" xlink:label="loc_karxStockIssuedDuringPeriodValueCommitmentSharesIssued_2935a1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_karxStockIssuedDuringPeriodValueCommitmentSharesIssued_2935a1" order="13" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AdjustmentToAdditionalPaidInCapitalCorrectionOfAPriorYearNoteConversion" xlink:label="loc_karxAdjustmentToAdditionalPaidInCapitalCorrectionOfAPriorYearNoteConversion_ef6385" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_karxAdjustmentToAdditionalPaidInCapitalCorrectionOfAPriorYearNoteConversion_ef6385" order="14" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AdjustmentToAdditionalPaidInCapitalReclassificationOfWarrantsToDerivativeLiabilities" xlink:label="loc_karxAdjustmentToAdditionalPaidInCapitalReclassificationOfWarrantsToDerivativeLiabilities_61193f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_karxAdjustmentToAdditionalPaidInCapitalReclassificationOfWarrantsToDerivativeLiabilities_61193f" order="15" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaapSharesIssued_16b4c7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapSharesIssued_16b4c7" order="16" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity_273010" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_5762e7" xlink:to="loc_us-gaapStockholdersEquity_273010" order="17" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CondensedConsolidatedStatementsOfCashFlowUnaudited" xlink:title="170000 - Statement - Condensed Consolidated Statements of Cash Flow (Unaudited)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaapNetCashProvidedByUsedInOperatingActivitiesAbstract_3c600c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapNetCashProvidedByUsedInOperatingActivitiesAbstract_3c600c" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss_5993c4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapNetIncomeLoss_5993c4" order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization" xlink:label="loc_us-gaapDepreciationAndAmortization_5feb20" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapDepreciationAndAmortization_5feb20" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense" xlink:label="loc_us-gaapOperatingLeaseRightOfUseAssetAmortizationExpense_9021d2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapOperatingLeaseRightOfUseAssetAmortizationExpense_9021d2" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:label="loc_us-gaapAmortizationOfFinancingCostsAndDiscounts_0d1baa" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapAmortizationOfFinancingCostsAndDiscounts_0d1baa" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeGainLossOnDerivativeNet" xlink:label="loc_us-gaapDerivativeGainLossOnDerivativeNet_2552ba" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapDerivativeGainLossOnDerivativeNet_2552ba" order="7" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestAndFeeIncomeOtherLoans" xlink:label="loc_us-gaapInterestAndFeeIncomeOtherLoans_9fc708" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapInterestAndFeeIncomeOtherLoans_9fc708" order="8" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="loc_us-gaapProvisionForDoubtfulAccounts_8e0def" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapProvisionForDoubtfulAccounts_8e0def" order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaapAllocatedShareBasedCompensationExpense_dcdcf1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapAllocatedShareBasedCompensationExpense_dcdcf1" order="10" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ContractFulfillmentAssetsExpense" xlink:label="loc_karxContractFulfillmentAssetsExpense_75af9c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_karxContractFulfillmentAssetsExpense_75af9c" order="11" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TotalOperatingLeaseExpense" xlink:label="loc_karxTotalOperatingLeaseExpense_02a7d5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_karxTotalOperatingLeaseExpense_02a7d5" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketableSecuritiesUnrealizedGainLoss" xlink:label="loc_us-gaapMarketableSecuritiesUnrealizedGainLoss_02a793" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapMarketableSecuritiesUnrealizedGainLoss_02a793" order="13" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SettlementOfInterestByApplicationOfPrepaidInterest" xlink:label="loc_karxSettlementOfInterestByApplicationOfPrepaidInterest_e98ce4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_karxSettlementOfInterestByApplicationOfPrepaidInterest_e98ce4" order="14" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FinanceChargesOnReceivablesFinancingObligations" xlink:label="loc_karxFinanceChargesOnReceivablesFinancingObligations_9cc183" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_karxFinanceChargesOnReceivablesFinancingObligations_9cc183" order="15" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ForeignCurrencyTransactionGainLossOnLoansUnrealized" xlink:label="loc_karxForeignCurrencyTransactionGainLossOnLoansUnrealized_b977c9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_karxForeignCurrencyTransactionGainLossOnLoansUnrealized_b977c9" order="16" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_7484e6" xlink:to="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaapIncreaseDecreaseInAccountsReceivable_614157" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInAccountsReceivable_614157" order="18" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="loc_us-gaapIncreaseDecreaseInInventories_f02d5e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInInventories_f02d5e" order="19" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:label="loc_us-gaapIncreaseDecreaseInPrepaidExpense_d25154" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInPrepaidExpense_d25154" order="20" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherCurrentAssets" xlink:label="loc_us-gaapIncreaseDecreaseInOtherCurrentAssets_bcd087" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInOtherCurrentAssets_bcd087" order="21" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="loc_us-gaapIncreaseDecreaseInAccountsPayable_fb6c21" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInAccountsPayable_fb6c21" order="22" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInDeferredRevenue" xlink:label="loc_us-gaapIncreaseDecreaseInDeferredRevenue_e14fa7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInDeferredRevenue_e14fa7" order="23" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInInterestPayableNet" xlink:label="loc_us-gaapIncreaseDecreaseInInterestPayableNet_f2b5f6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInInterestPayableNet_f2b5f6" order="24" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherCurrentLiabilities" xlink:label="loc_us-gaapIncreaseDecreaseInOtherCurrentLiabilities_1fe777" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInOtherCurrentLiabilities_1fe777" order="25" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:label="loc_us-gaapIncreaseDecreaseInOtherOperatingAssets_9c6776" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapIncreaseDecreaseInOtherOperatingAssets_9c6776" order="26" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInOperatingActivities_6af77e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapIncreaseDecreaseInOperatingCapitalAbstract_c16b24" xlink:to="loc_us-gaapNetCashProvidedByUsedInOperatingActivities_6af77e" order="27" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="loc_us-gaapNetCashProvidedByUsedInInvestingActivitiesAbstract_227eff" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapNetCashProvidedByUsedInInvestingActivitiesAbstract_227eff" order="28" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaapPaymentsToAcquirePropertyPlantAndEquipment_1ab3b0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInInvestingActivitiesAbstract_227eff" xlink:to="loc_us-gaapPaymentsToAcquirePropertyPlantAndEquipment_1ab3b0" order="29" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CapitalizedAppDevelopmentCosts" xlink:label="loc_karxCapitalizedAppDevelopmentCosts_2e1588" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInInvestingActivitiesAbstract_227eff" xlink:to="loc_karxCapitalizedAppDevelopmentCosts_2e1588" order="30" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireProjects" xlink:label="loc_us-gaapPaymentsToAcquireProjects_5fb7cb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInInvestingActivitiesAbstract_227eff" xlink:to="loc_us-gaapPaymentsToAcquireProjects_5fb7cb" order="31" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInInvestingActivities_367641" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInInvestingActivitiesAbstract_227eff" xlink:to="loc_us-gaapNetCashProvidedByUsedInInvestingActivities_367641" order="32" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" order="33" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromConvertibleDebt" xlink:label="loc_us-gaapProceedsFromConvertibleDebt_e70124" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapProceedsFromConvertibleDebt_e70124" order="34" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfConvertibleDebt" xlink:label="loc_us-gaapRepaymentsOfConvertibleDebt_51ef56" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapRepaymentsOfConvertibleDebt_51ef56" order="35" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:label="loc_us-gaapProceedsFromIssuanceOfLongTermDebt_3ea7a4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapProceedsFromIssuanceOfLongTermDebt_3ea7a4" order="36" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfLongTermDebt" xlink:label="loc_us-gaapRepaymentsOfLongTermDebt_2c88c7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapRepaymentsOfLongTermDebt_2c88c7" order="37" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProceedsFromRepaymentsOfReceivablesFinancingObligationsNet" xlink:label="loc_karxProceedsFromRepaymentsOfReceivablesFinancingObligationsNet_a18da2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_karxProceedsFromRepaymentsOfReceivablesFinancingObligationsNet_a18da2" order="38" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromShortTermDebt" xlink:label="loc_us-gaapProceedsFromShortTermDebt_938275" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapProceedsFromShortTermDebt_938275" order="39" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromRelatedPartyDebt" xlink:label="loc_us-gaapProceedsFromRelatedPartyDebt_a2754d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapProceedsFromRelatedPartyDebt_a2754d" order="40" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaapProceedsFromIssuanceOfCommonStock_9fe4ad" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapProceedsFromIssuanceOfCommonStock_9fe4ad" order="41" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInFinancingActivities_73f91a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivitiesAbstract_0c1c40" xlink:to="loc_us-gaapNetCashProvidedByUsedInFinancingActivities_73f91a" order="42" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaapEffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_5cb817" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapEffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_5cb817" order="43" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_594cf8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_594cf8" order="44" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_023bce" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_023bce" order="45" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_f61139" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_f61139" order="46" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:label="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" order="47" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IssuanceOfSharesUponConvertibleLoanPrincipalAndInterest" xlink:label="loc_karxIssuanceOfSharesUponConvertibleLoanPrincipalAndInterest_450fcc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxIssuanceOfSharesUponConvertibleLoanPrincipalAndInterest_450fcc" order="48" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RecognitionOfDebtDiscountAtIssuanceEmbeddedDerivativeLiabilities" xlink:label="loc_karxRecognitionOfDebtDiscountAtIssuanceEmbeddedDerivativeLiabilities_11c5bf" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxRecognitionOfDebtDiscountAtIssuanceEmbeddedDerivativeLiabilities_11c5bf" order="49" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IssuanceOfSharesInConnectionWithNoteFinancings" xlink:label="loc_karxIssuanceOfSharesInConnectionWithNoteFinancings_21e02e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxIssuanceOfSharesInConnectionWithNoteFinancings_21e02e" order="50" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SettlementOfSecuritiesReceivableInEquitySecurities" xlink:label="loc_karxSettlementOfSecuritiesReceivableInEquitySecurities_bf074e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxSettlementOfSecuritiesReceivableInEquitySecurities_bf074e" order="51" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConversionOfReceivableAndDeferredRentIntoAConvertibleNoteReceivable" xlink:label="loc_karxConversionOfReceivableAndDeferredRentIntoAConvertibleNoteReceivable_7389b2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxConversionOfReceivableAndDeferredRentIntoAConvertibleNoteReceivable_7389b2" order="52" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CorrectionOfAPriorYearNoteConversion" xlink:label="loc_karxCorrectionOfAPriorYearNoteConversion_1e9ce0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxCorrectionOfAPriorYearNoteConversion_1e9ce0" order="53" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsReclassifiedFromEquityToDerivativeLiabilities" xlink:label="loc_karxWarrantsReclassifiedFromEquityToDerivativeLiabilities_aad7ad" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxWarrantsReclassifiedFromEquityToDerivativeLiabilities_aad7ad" order="54" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MaintenanceFeesEarnedAndSettledAgainstConvertibleNotesPayableAndAccruedInterest" xlink:label="loc_karxMaintenanceFeesEarnedAndSettledAgainstConvertibleNotesPayableAndAccruedInterest_5b175d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapNoncashInvestingAndFinancingItemsAbstract_24a182" xlink:to="loc_karxMaintenanceFeesEarnedAndSettledAgainstConvertibleNotesPayableAndAccruedInterest_5b175d" order="55" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SupplementalCashFlowInformationAbstract" xlink:label="loc_us-gaapSupplementalCashFlowInformationAbstract_15ebc0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapSupplementalCashFlowInformationAbstract_15ebc0" order="56" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPaidNet" xlink:label="loc_us-gaapInterestPaidNet_a22ba0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapSupplementalCashFlowInformationAbstract_15ebc0" xlink:to="loc_us-gaapInterestPaidNet_a22ba0" order="57" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxesPaidNet" xlink:label="loc_us-gaapIncomeTaxesPaidNet_34bb84" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementOfCashFlowsAbstract_16dd0e" xlink:to="loc_us-gaapIncomeTaxesPaidNet_34bb84" order="58" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements" xlink:title="995445 - Disclosure - Insider Trading Arrangements">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_InsiderTradingArrLineItems" xlink:label="loc_ecdInsiderTradingArrLineItems_13b663" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_Rule10b51ArrAdoptedFlag" xlink:label="loc_ecdRule10b51ArrAdoptedFlag_e9899e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_ecdInsiderTradingArrLineItems_13b663" xlink:to="loc_ecdRule10b51ArrAdoptedFlag_e9899e" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_Rule10b51ArrTrmntdFlag" xlink:label="loc_ecdRule10b51ArrTrmntdFlag_00c43d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_ecdInsiderTradingArrLineItems_13b663" xlink:to="loc_ecdRule10b51ArrTrmntdFlag_00c43d" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_NonRule10b51ArrAdoptedFlag" xlink:label="loc_ecdNonRule10b51ArrAdoptedFlag_8fbdf8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_ecdInsiderTradingArrLineItems_13b663" xlink:to="loc_ecdNonRule10b51ArrAdoptedFlag_8fbdf8" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_NonRule10b51ArrTrmntdFlag" xlink:label="loc_ecdNonRule10b51ArrTrmntdFlag_f63b33" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_ecdInsiderTradingArrLineItems_13b663" xlink:to="loc_ecdNonRule10b51ArrTrmntdFlag_f63b33" order="5" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPolicies" xlink:title="995446 - Disclosure - Basis of Presentation and Significant Accounting Policies">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_74a230" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaapSignificantAccountingPoliciesTextBlock_f40bf9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_74a230" xlink:to="loc_us-gaapSignificantAccountingPoliciesTextBlock_f40bf9" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/PrepaidExpenses" xlink:title="995447 - Disclosure - Prepaid Expenses">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseCurrentAbstract" xlink:label="loc_us-gaapPrepaidExpenseCurrentAbstract_c9d275" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PrepaidExpensesDisclosureTextBlock" xlink:label="loc_karxPrepaidExpensesDisclosureTextBlock_8563fc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPrepaidExpenseCurrentAbstract_c9d275" xlink:to="loc_karxPrepaidExpensesDisclosureTextBlock_8563fc" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/Inventory" xlink:title="995448 - Disclosure - Inventory">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaapInventoryDisclosureAbstract_96191d" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryDisclosureTextBlock" xlink:label="loc_us-gaapInventoryDisclosureTextBlock_2e2e5b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInventoryDisclosureAbstract_96191d" xlink:to="loc_us-gaapInventoryDisclosureTextBlock_2e2e5b" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/PropertyAndEquipment" xlink:title="995449 - Disclosure - Property and Equipment">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PropertyAndEquipmentAbstract" xlink:label="loc_karxPropertyAndEquipmentAbstract_dc13a3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:label="loc_us-gaapPropertyPlantAndEquipmentDisclosureTextBlock_e4b259" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_dc13a3" xlink:to="loc_us-gaapPropertyPlantAndEquipmentDisclosureTextBlock_e4b259" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/AcquiredProjectPipeline" xlink:title="995450 - Disclosure - Acquired Project Pipeline">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AcquiredProjectPipelineAbstract" xlink:label="loc_karxAcquiredProjectPipelineAbstract_c835b6" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AcquiredProjectPipelineDisclosureTextBlock" xlink:label="loc_karxAcquiredProjectPipelineDisclosureTextBlock_d2dbeb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_c835b6" xlink:to="loc_karxAcquiredProjectPipelineDisclosureTextBlock_d2dbeb" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ContractFulfillmentAssets" xlink:title="995451 - Disclosure - Contract Fulfillment Assets">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ContractFulfillmentAssetsAbstract" xlink:label="loc_karxContractFulfillmentAssetsAbstract_8550cb" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ContractFulfillmentAssetstDisclosureTextBlock" xlink:label="loc_karxContractFulfillmentAssetstDisclosureTextBlock_c7f65e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxContractFulfillmentAssetsAbstract_8550cb" xlink:to="loc_karxContractFulfillmentAssetstDisclosureTextBlock_c7f65e" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomer" xlink:title="995452 - Disclosure - Other Assets, Maintenance Agreement and Consideration Payable to a Customer">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract" xlink:label="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_914a56" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:label="loc_us-gaapRevenueFromContractWithCustomerTextBlock_872542" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_914a56" xlink:to="loc_us-gaapRevenueFromContractWithCustomerTextBlock_872542" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LoanReceivable" xlink:title="995453 - Disclosure - Loan Receivable">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LoanReceivableAbstract" xlink:label="loc_karxLoanReceivableAbstract_bef65f" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LoanReceivableDisclosureTextBlock" xlink:label="loc_karxLoanReceivableDisclosureTextBlock_a33109" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxLoanReceivableAbstract_bef65f" xlink:to="loc_karxLoanReceivableDisclosureTextBlock_a33109" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/DeferredRevenue" xlink:title="995454 - Disclosure - Deferred Revenue">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueAbstract" xlink:label="loc_us-gaapDeferredRevenueAbstract_de1c41" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueDisclosureTextBlock" xlink:label="loc_us-gaapDeferredRevenueDisclosureTextBlock_422b76" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_de1c41" xlink:to="loc_us-gaapDeferredRevenueDisclosureTextBlock_422b76" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherCurrentLiabilities" xlink:title="995455 - Disclosure - Other Current Liabilities">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherCurrentLiabilitiesAbstract" xlink:label="loc_karxOtherCurrentLiabilitiesAbstract_2bdde9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesDisclosureTextBlock" xlink:label="loc_us-gaapOtherLiabilitiesDisclosureTextBlock_0001af" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_2bdde9" xlink:to="loc_us-gaapOtherLiabilitiesDisclosureTextBlock_0001af" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ConvertibleNotes" xlink:title="995456 - Disclosure - Convertible Notes">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleDebtAbstract" xlink:label="loc_karxConvertibleDebtAbstract_1dc7fa" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleNotesDisclosureTextBlock" xlink:label="loc_karxConvertibleNotesDisclosureTextBlock_54d126" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxConvertibleDebtAbstract_1dc7fa" xlink:to="loc_karxConvertibleNotesDisclosureTextBlock_54d126" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LongTermDebt" xlink:title="995457 - Disclosure - Long-Term Debt">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtAbstract" xlink:label="loc_us-gaapLongTermDebtAbstract_1f98de" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtTextBlock" xlink:label="loc_us-gaapLongTermDebtTextBlock_93f0b3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLongTermDebtAbstract_1f98de" xlink:to="loc_us-gaapLongTermDebtTextBlock_93f0b3" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoan" xlink:title="995458 - Disclosure - Receivables Financing Obligations and Term Loan">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReceivablesFinancingObligationsAbstract" xlink:label="loc_karxReceivablesFinancingObligationsAbstract_e80a30" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReceivablesFinancingObligationsDisclosureTextBlock" xlink:label="loc_karxReceivablesFinancingObligationsDisclosureTextBlock_051b67" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxReceivablesFinancingObligationsAbstract_e80a30" xlink:to="loc_karxReceivablesFinancingObligationsDisclosureTextBlock_051b67" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ShareholdersEquity" xlink:title="995459 - Disclosure - Shareholders Equity">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareholdersEquityAbstract" xlink:label="loc_karxShareholdersEquityAbstract_239d82" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="loc_us-gaapStockholdersEquityNoteDisclosureTextBlock_99b85f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_239d82" xlink:to="loc_us-gaapStockholdersEquityNoteDisclosureTextBlock_99b85f" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/Warrants" xlink:title="995460 - Disclosure - Warrants">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsAbstract" xlink:label="loc_karxWarrantsAbstract_4b6299" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsTextBlock" xlink:label="loc_karxWarrantsTextBlock_f2e33b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_4b6299" xlink:to="loc_karxWarrantsTextBlock_f2e33b" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InvestmentsAndSecuritiesReceivable" xlink:title="995461 - Disclosure - Investments and Securities Receivable">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentsAbstract" xlink:label="loc_us-gaapInvestmentsAbstract_ef3028" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:label="loc_us-gaapInvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_fbf229" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_ef3028" xlink:to="loc_us-gaapInvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_fbf229" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InternallyDevelopedSoftware" xlink:title="995462 - Disclosure - Internally Developed Software">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_InternallyDevelopedSoftwareAbstract" xlink:label="loc_karxInternallyDevelopedSoftwareAbstract_609f4d" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsDisclosureTextBlock" xlink:label="loc_us-gaapIntangibleAssetsDisclosureTextBlock_a263fd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxInternallyDevelopedSoftwareAbstract_609f4d" xlink:to="loc_us-gaapIntangibleAssetsDisclosureTextBlock_a263fd" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/StockOptionPlan" xlink:title="995463 - Disclosure - Stock Option Plan">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockOptionPlanAbstract" xlink:label="loc_karxStockOptionPlanAbstract_9d778d" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:label="loc_us-gaapDisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_5ab0e9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxStockOptionPlanAbstract_9d778d" xlink:to="loc_us-gaapDisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_5ab0e9" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/IncomeTaxes" xlink:title="995464 - Disclosure - Income Taxes">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IncomeTaxesAbstract" xlink:label="loc_karxIncomeTaxesAbstract_c04fca" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxDisclosureTextBlock" xlink:label="loc_us-gaapIncomeTaxDisclosureTextBlock_a04ab5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxIncomeTaxesAbstract_c04fca" xlink:to="loc_us-gaapIncomeTaxDisclosureTextBlock_a04ab5" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LossPerShare" xlink:title="995465 - Disclosure - Loss Per Share">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaapEarningsPerShareAbstract_4af501" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareTextBlock" xlink:label="loc_us-gaapEarningsPerShareTextBlock_6b6236" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEarningsPerShareAbstract_4af501" xlink:to="loc_us-gaapEarningsPerShareTextBlock_6b6236" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/RelatedPartyTransactions" xlink:title="995466 - Disclosure - Related Party Transactions">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="loc_us-gaapRelatedPartyTransactionsAbstract_20ae3f" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:label="loc_us-gaapRelatedPartyTransactionsDisclosureTextBlock_459e22" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionsAbstract_20ae3f" xlink:to="loc_us-gaapRelatedPartyTransactionsDisclosureTextBlock_459e22" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/Concentrations" xlink:title="995467 - Disclosure - Concentrations">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RisksAndUncertaintiesAbstract" xlink:label="loc_us-gaapRisksAndUncertaintiesAbstract_24bd39" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskDisclosureTextBlock" xlink:label="loc_us-gaapConcentrationRiskDisclosureTextBlock_f7b871" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRisksAndUncertaintiesAbstract_24bd39" xlink:to="loc_us-gaapConcentrationRiskDisclosureTextBlock_f7b871" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CommitmentsAndContingencies" xlink:title="995468 - Disclosure - Commitments and Contingencies">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_eee4f8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="loc_us-gaapCommitmentsAndContingenciesDisclosureTextBlock_c99eb2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_eee4f8" xlink:to="loc_us-gaapCommitmentsAndContingenciesDisclosureTextBlock_c99eb2" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/SubsequentEvents" xlink:title="995469 - Disclosure - Subsequent Events">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaapSubsequentEventsAbstract_6f42b6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaapSubsequentEventsTextBlock_fcdaf6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapSubsequentEventsAbstract_6f42b6" xlink:to="loc_us-gaapSubsequentEventsTextBlock_fcdaf6" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesPolicies" xlink:title="995470 - Disclosure - Basis of Presentation and Significant Accounting Policies (Policies)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_9ad384" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_GoingConcernPolicyTextBlock" xlink:label="loc_karxGoingConcernPolicyTextBlock_db75be" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_karxGoingConcernPolicyTextBlock_db75be" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:label="loc_us-gaapBasisOfAccountingPolicyPolicyTextBlock_2f7662" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapBasisOfAccountingPolicyPolicyTextBlock_2f7662" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UseOfEstimates" xlink:label="loc_us-gaapUseOfEstimates_3650b7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapUseOfEstimates_3650b7" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:label="loc_us-gaapFairValueOfFinancialInstrumentsPolicy_b7a314" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapFairValueOfFinancialInstrumentsPolicy_b7a314" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRecognitionPolicyTextBlock" xlink:label="loc_us-gaapRevenueRecognitionPolicyTextBlock_c5867a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapRevenueRecognitionPolicyTextBlock_c5867a" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" xlink:label="loc_us-gaapForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_191231" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_191231" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerSharePolicyTextBlock" xlink:label="loc_us-gaapEarningsPerSharePolicyTextBlock_aa41a8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapEarningsPerSharePolicyTextBlock_aa41a8" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingPolicyPolicyTextBlock" xlink:label="loc_us-gaapSegmentReportingPolicyPolicyTextBlock_3910b9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapSegmentReportingPolicyPolicyTextBlock_3910b9" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Reclassifications" xlink:label="loc_us-gaapReclassifications_9227bb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapReclassifications_9227bb" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaapNewAccountingPronouncementsPolicyPolicyTextBlock_1e8ca6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_9ad384" xlink:to="loc_us-gaapNewAccountingPronouncementsPolicyPolicyTextBlock_1e8ca6" order="10" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesTables" xlink:title="995471 - Disclosure - Basis of Presentation and Significant Accounting Policies (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_075ab7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisTextBlock" xlink:label="loc_us-gaapFairValueLiabilitiesMeasuredOnRecurringBasisTextBlock_d6ed7d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_075ab7" xlink:to="loc_us-gaapFairValueLiabilitiesMeasuredOnRecurringBasisTextBlock_d6ed7d" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfDerivativeLiabilitiesAtFairValueTableTextBlock" xlink:label="loc_us-gaapScheduleOfDerivativeLiabilitiesAtFairValueTableTextBlock_595e39" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_075ab7" xlink:to="loc_us-gaapScheduleOfDerivativeLiabilitiesAtFairValueTableTextBlock_595e39" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:label="loc_us-gaapDisaggregationOfRevenueTableTextBlock_4561d6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_075ab7" xlink:to="loc_us-gaapDisaggregationOfRevenueTableTextBlock_4561d6" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock" xlink:label="loc_us-gaapScheduleOfSegmentReportingInformationBySegmentTextBlock_bf65f9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_075ab7" xlink:to="loc_us-gaapScheduleOfSegmentReportingInformationBySegmentTextBlock_bf65f9" order="4" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/PrepaidExpensesTables" xlink:title="995472 - Disclosure - Prepaid Expenses (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseCurrentAbstract" xlink:label="loc_us-gaapPrepaidExpenseCurrentAbstract_d45ece" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ScheduleOfPrepaidExpensesTableTextBlock" xlink:label="loc_karxScheduleOfPrepaidExpensesTableTextBlock_43c7e3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPrepaidExpenseCurrentAbstract_d45ece" xlink:to="loc_karxScheduleOfPrepaidExpensesTableTextBlock_43c7e3" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InventoryTables" xlink:title="995473 - Disclosure - Inventory (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaapInventoryDisclosureAbstract_12bfdd" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xlink:label="loc_us-gaapScheduleOfInventoryCurrentTableTextBlock_4099f1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInventoryDisclosureAbstract_12bfdd" xlink:to="loc_us-gaapScheduleOfInventoryCurrentTableTextBlock_4099f1" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/PropertyAndEquipmentTables" xlink:title="995474 - Disclosure - Property and Equipment (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PropertyAndEquipmentAbstract" xlink:label="loc_karxPropertyAndEquipmentAbstract_f54077" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTextBlock_dd1d2c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_f54077" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTextBlock_dd1d2c" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/AcquiredProjectPipelineTables" xlink:title="995475 - Disclosure - Acquired Project Pipeline (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AcquiredProjectPipelineAbstract" xlink:label="loc_karxAcquiredProjectPipelineAbstract_0fceb1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:label="loc_us-gaapScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_ae20da" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_0fceb1" xlink:to="loc_us-gaapScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_ae20da" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ContractFulfillmentAssetsTables" xlink:title="995476 - Disclosure - Contract Fulfillment Assets (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ContractFulfillmentAssetsAbstract" xlink:label="loc_karxContractFulfillmentAssetsAbstract_e887bc" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ScheduleOfContractFulfillmentAssetsTableTextBlock" xlink:label="loc_karxScheduleOfContractFulfillmentAssetsTableTextBlock_f20147" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxContractFulfillmentAssetsAbstract_e887bc" xlink:to="loc_karxScheduleOfContractFulfillmentAssetsTableTextBlock_f20147" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerTables" xlink:title="995477 - Disclosure - Other Assets Maintenance Agreement and Consideration Payable to a Customer (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ContractAssetMaintenanceAgreementAbstract" xlink:label="loc_karxContractAssetMaintenanceAgreementAbstract_d56f7c" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfOtherAssetsTableTextBlock" xlink:label="loc_us-gaapScheduleOfOtherAssetsTableTextBlock_13d885" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxContractAssetMaintenanceAgreementAbstract_d56f7c" xlink:to="loc_us-gaapScheduleOfOtherAssetsTableTextBlock_13d885" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/DeferredRevenueTables" xlink:title="995478 - Disclosure - Deferred Revenue (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueAbstract" xlink:label="loc_us-gaapDeferredRevenueAbstract_6bc207" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ScheduleOfDeferredRevenueTableTextBlock" xlink:label="loc_karxScheduleOfDeferredRevenueTableTextBlock_4a435b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_6bc207" xlink:to="loc_karxScheduleOfDeferredRevenueTableTextBlock_4a435b" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherCurrentLiabilitiesTables" xlink:title="995479 - Disclosure - Other Current Liabilities (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherCurrentLiabilitiesAbstract" xlink:label="loc_karxOtherCurrentLiabilitiesAbstract_6814f2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCurrentLiabilitiesTableTextBlock" xlink:label="loc_us-gaapOtherCurrentLiabilitiesTableTextBlock_dcd3aa" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_6814f2" xlink:to="loc_us-gaapOtherCurrentLiabilitiesTableTextBlock_dcd3aa" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ConvertibleNotesTables" xlink:title="995480 - Disclosure - Convertible Notes (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleDebtAbstract" xlink:label="loc_karxConvertibleDebtAbstract_121d3b" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfDebtTableTextBlock" xlink:label="loc_us-gaapScheduleOfDebtTableTextBlock_3c2c3d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxConvertibleDebtAbstract_121d3b" xlink:to="loc_us-gaapScheduleOfDebtTableTextBlock_3c2c3d" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LongTermDebtTables" xlink:title="995481 - Disclosure - Long-Term Debt (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtAbstract" xlink:label="loc_us-gaapLongTermDebtAbstract_5ff069" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ScheduleOfLongTermDebtTableTextBlock" xlink:label="loc_karxScheduleOfLongTermDebtTableTextBlock_8dd943" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLongTermDebtAbstract_5ff069" xlink:to="loc_karxScheduleOfLongTermDebtTableTextBlock_8dd943" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoanTables" xlink:title="995482 - Disclosure - Receivables Financing Obligations and Term Loan (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReceivablesFinancingObligationsAbstract" xlink:label="loc_karxReceivablesFinancingObligationsAbstract_3742d8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_FinancingReceivableCreditRatioTableTextBlock" xlink:label="loc_srtFinancingReceivableCreditRatioTableTextBlock_e66a74" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxReceivablesFinancingObligationsAbstract_3742d8" xlink:to="loc_srtFinancingReceivableCreditRatioTableTextBlock_e66a74" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/WarrantsTables" xlink:title="995483 - Disclosure - Warrants (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsAbstract" xlink:label="loc_karxWarrantsAbstract_371be5" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ScheduleOfWarrantsTableTextBlock" xlink:label="loc_karxScheduleOfWarrantsTableTextBlock_c123a5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_371be5" xlink:to="loc_karxScheduleOfWarrantsTableTextBlock_c123a5" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InvestmentsAndSecuritiesReceivableTables" xlink:title="995484 - Disclosure - Investments and Securities Receivable (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentsAbstract" xlink:label="loc_us-gaapInvestmentsAbstract_6b7fa8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentTableTextBlock" xlink:label="loc_us-gaapInvestmentTableTextBlock_51852f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_6b7fa8" xlink:to="loc_us-gaapInvestmentTableTextBlock_51852f" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/StockOptionPlanTables" xlink:title="995485 - Disclosure - Stock Option Plan (Tables)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockOptionPlanAbstract" xlink:label="loc_karxStockOptionPlanAbstract_20cb74" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" xlink:label="loc_us-gaapScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_4da7c3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxStockOptionPlanAbstract_20cb74" xlink:to="loc_us-gaapScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_4da7c3" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LossPerShareTables" xlink:title="995486 - Disclosure - Loss Per Share (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaapEarningsPerShareAbstract_a37eef" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairmentEffectsOnEarningsPerShareTableTextBlock" xlink:label="loc_us-gaapImpairmentEffectsOnEarningsPerShareTableTextBlock_1d2154" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEarningsPerShareAbstract_a37eef" xlink:to="loc_us-gaapImpairmentEffectsOnEarningsPerShareTableTextBlock_1d2154" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CommitmentsAndContingenciesTables" xlink:title="995487 - Disclosure - Commitments and Contingencies (Tables)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_f75725" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityMaturityTableTextBlock_4304da" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_f75725" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityMaturityTableTextBlock_4304da" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails" xlink:title="995488 - Disclosure - Basis of Presentation and Significant Accounting Policies (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_aed280" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_cad74f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_aed280" xlink:to="loc_us-gaapStatementTable_cad74f" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_cbc53f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_cad74f" xlink:to="loc_us-gaapStatementLineItems_cbc53f" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaapFairValueByFairValueHierarchyLevelAxis_dbdf4e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_cad74f" xlink:to="loc_us-gaapFairValueByFairValueHierarchyLevelAxis_dbdf4e" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_0713ea" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFairValueByFairValueHierarchyLevelAxis_dbdf4e" xlink:to="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_0713ea" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaapFairValueInputsLevel1Member_bfee02" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_0713ea" xlink:to="loc_us-gaapFairValueInputsLevel1Member_bfee02" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaapFairValueInputsLevel2Member_9db35b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_0713ea" xlink:to="loc_us-gaapFairValueInputsLevel2Member_9db35b" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaapFairValueInputsLevel3Member_9c829e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_0713ea" xlink:to="loc_us-gaapFairValueInputsLevel3Member_9c829e" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityMethodInvestmentsFairValueDisclosure" xlink:label="loc_us-gaapEquityMethodInvestmentsFairValueDisclosure_80b18a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_cbc53f" xlink:to="loc_us-gaapEquityMethodInvestmentsFairValueDisclosure_80b18a" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilityFairValueOfCollateral" xlink:label="loc_us-gaapDerivativeLiabilityFairValueOfCollateral_471476" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_cbc53f" xlink:to="loc_us-gaapDerivativeLiabilityFairValueOfCollateral_471476" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DerivativeLiabilitiesWarrants" xlink:label="loc_karxDerivativeLiabilitiesWarrants_08aefc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_cbc53f" xlink:to="loc_karxDerivativeLiabilitiesWarrants_08aefc" order="3" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails1" xlink:title="995489 - Disclosure - Basis of Presentation and Significant Accounting Policies (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_f4aef0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:label="loc_us-gaapFairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_1ae22e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_f4aef0" xlink:to="loc_us-gaapFairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_1ae22e" order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FairValueMeasurementRecognizedOnIssuanceOfConvertibleNotes" xlink:label="loc_karxFairValueMeasurementRecognizedOnIssuanceOfConvertibleNotes_f61ed5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_f4aef0" xlink:to="loc_karxFairValueMeasurementRecognizedOnIssuanceOfConvertibleNotes_f61ed5" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FairValueMeasurementReleasedToEquityOnConversion" xlink:label="loc_karxFairValueMeasurementReleasedToEquityOnConversion_03e4d6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_f4aef0" xlink:to="loc_karxFairValueMeasurementReleasedToEquityOnConversion_03e4d6" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReclassificationOfWarrantsFromEquityAmount" xlink:label="loc_karxReclassificationOfWarrantsFromEquityAmount_19858a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_f4aef0" xlink:to="loc_karxReclassificationOfWarrantsFromEquityAmount_19858a" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease" xlink:label="loc_us-gaapFairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease_d2edda" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_f4aef0" xlink:to="loc_us-gaapFairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease_d2edda" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:label="loc_us-gaapFairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_371aec" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_f4aef0" xlink:to="loc_us-gaapFairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_371aec" order="6" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails2" xlink:title="995490 - Disclosure - Basis of Presentation and Significant Accounting Policies (Details 2)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_105248" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_cb92d2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_105248" xlink:to="loc_us-gaapStatementTable_cb92d2" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_9797ae" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_cb92d2" xlink:to="loc_us-gaapStatementLineItems_9797ae" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srtStatementGeographicalAxis_356e1f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_cb92d2" xlink:to="loc_srtStatementGeographicalAxis_356e1f" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srtSegmentGeographicalDomain_5cf0b5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtStatementGeographicalAxis_356e1f" xlink:to="loc_srtSegmentGeographicalDomain_5cf0b5" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US" xlink:label="loc_countryUS_7aee92" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtSegmentGeographicalDomain_5cf0b5" xlink:to="loc_countryUS_7aee92" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_CY" xlink:label="loc_countryCY_8f045c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtSegmentGeographicalDomain_5cf0b5" xlink:to="loc_countryCY_8f045c" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_IE" xlink:label="loc_countryIE_513595" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtSegmentGeographicalDomain_5cf0b5" xlink:to="loc_countryIE_513595" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_ES" xlink:label="loc_countryES_0b4bb2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtSegmentGeographicalDomain_5cf0b5" xlink:to="loc_countryES_0b4bb2" order="1024" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_CA" xlink:label="loc_countryCA_9bf8fd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtSegmentGeographicalDomain_5cf0b5" xlink:to="loc_countryCA_9bf8fd" order="1025" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_CO" xlink:label="loc_countryCO_c2e6ef" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtSegmentGeographicalDomain_5cf0b5" xlink:to="loc_countryCO_c2e6ef" order="1026" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues_1e9a0b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9797ae" xlink:to="loc_us-gaapRevenues_1e9a0b" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails3" xlink:title="995491 - Disclosure - Basis of Presentation and Significant Accounting Policies (Details 3)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_ce7cba" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_c75792" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_ce7cba" xlink:to="loc_us-gaapStatementTable_c75792" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_66f66d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_c75792" xlink:to="loc_us-gaapStatementLineItems_66f66d" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsConsolidationItemsAxis" xlink:label="loc_us-gaapSubsegmentsConsolidationItemsAxis_81e226" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_c75792" xlink:to="loc_us-gaapSubsegmentsConsolidationItemsAxis_81e226" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsConsolidationItemsDomain" xlink:label="loc_us-gaapSubsegmentsConsolidationItemsDomain_f88c41" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapSubsegmentsConsolidationItemsAxis_81e226" xlink:to="loc_us-gaapSubsegmentsConsolidationItemsDomain_f88c41" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportableSubsegmentsMember" xlink:label="loc_us-gaapReportableSubsegmentsMember_af74f2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapSubsegmentsConsolidationItemsDomain_f88c41" xlink:to="loc_us-gaapReportableSubsegmentsMember_af74f2" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues_36fc03" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapRevenues_36fc03" order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaapCostOfRevenue_ca02b2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapCostOfRevenue_ca02b2" order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalariesWagesAndOfficersCompensation" xlink:label="loc_us-gaapSalariesWagesAndOfficersCompensation_9ec1ef" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapSalariesWagesAndOfficersCompensation_9ec1ef" order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaapShareBasedCompensation_c0112b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapShareBasedCompensation_c0112b" order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketingExpense" xlink:label="loc_us-gaapMarketingExpense_5e6454" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapMarketingExpense_5e6454" order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProfessionalFees" xlink:label="loc_us-gaapProfessionalFees_fa9736" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapProfessionalFees_fa9736" order="6" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TravelAndEntertainmentExpense" xlink:label="loc_us-gaapTravelAndEntertainmentExpense_4ed36a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapTravelAndEntertainmentExpense_4ed36a" order="7" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization" xlink:label="loc_us-gaapDepreciationAndAmortization_728cd1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapDepreciationAndAmortization_728cd1" order="8" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RentExpense" xlink:label="loc_karxRentExpense_2f541e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_karxRentExpense_2f541e" order="9" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DuesAndSubscriptionsAmount" xlink:label="loc_karxDuesAndSubscriptionsAmount_b7d0f3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_karxDuesAndSubscriptionsAmount_b7d0f3" order="10" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_BankAndTransactionFees" xlink:label="loc_karxBankAndTransactionFees_cc685b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_karxBankAndTransactionFees_cc685b" order="11" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProvisionForOtherCreditLosses" xlink:label="loc_us-gaapProvisionForOtherCreditLosses_bad58b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapProvisionForOtherCreditLosses_bad58b" order="12" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCostAndExpenseOperating" xlink:label="loc_us-gaapOtherCostAndExpenseOperating_82a2d3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapOtherCostAndExpenseOperating_82a2d3" order="13" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SignificantSegmentExpenses" xlink:label="loc_karxSignificantSegmentExpenses_48d38c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_karxSignificantSegmentExpenses_48d38c" order="14" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RevenueLessSignificantSegmentExpensesAmount" xlink:label="loc_karxRevenueLessSignificantSegmentExpensesAmount_95228a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_karxRevenueLessSignificantSegmentExpensesAmount_95228a" order="15" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingOtherItemAmount" xlink:label="loc_us-gaapSegmentReportingOtherItemAmount_1a2d35" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapSegmentReportingOtherItemAmount_1a2d35" order="16" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss_f683e4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_66f66d" xlink:to="loc_us-gaapNetIncomeLoss_f683e4" order="17" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetailsNarrative" xlink:title="995492 - Disclosure - Basis of Presentation and Significant Accounting Policies (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaapAccountingPoliciesAbstract_6b6407" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_64b478" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountingPoliciesAbstract_6b6407" xlink:to="loc_us-gaapStatementTable_64b478" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_9b8de5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_64b478" xlink:to="loc_us-gaapStatementLineItems_9b8de5" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis_4af3ca" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_64b478" xlink:to="loc_us-gaapPlanNameAxis_4af3ca" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_830ecb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameAxis_4af3ca" xlink:to="loc_us-gaapPlanNameDomain_830ecb" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaapDebtInstrumentAxis_cffff3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_64b478" xlink:to="loc_us-gaapDebtInstrumentAxis_cffff3" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaapDebtInstrumentNameDomain_baca5c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDebtInstrumentAxis_cffff3" xlink:to="loc_us-gaapDebtInstrumentNameDomain_baca5c" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_715bee" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_64b478" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_715bee" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_b15d9b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_715bee" xlink:to="loc_us-gaapRelatedPartyDomain_b15d9b" order="1060" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MasterNoteTranchesOneMember" xlink:label="loc_karxMasterNoteTranchesOneMember_f10438" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_830ecb" xlink:to="loc_karxMasterNoteTranchesOneMember_f10438" order="1061" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FiveNotesMember" xlink:label="loc_karxFiveNotesMember_0240a1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_830ecb" xlink:to="loc_karxFiveNotesMember_0240a1" order="1062" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleNotesMember" xlink:label="loc_karxConvertibleNotesMember_ac5365" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDebtInstrumentNameDomain_baca5c" xlink:to="loc_karxConvertibleNotesMember_ac5365" order="1063" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MaintenanceAgreementMember" xlink:label="loc_karxMaintenanceAgreementMember_a9c04e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_b15d9b" xlink:to="loc_karxMaintenanceAgreementMember_a9c04e" order="1064" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit_9746bc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit_9746bc" order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WorkingCapitalDeficit" xlink:label="loc_karxWorkingCapitalDeficit_9b83f0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxWorkingCapitalDeficit_9b83f0" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Cash" xlink:label="loc_us-gaapCash_98221e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_us-gaapCash_98221e" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaapShareBasedCompensation_567e43" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_us-gaapShareBasedCompensation_567e43" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueIssuedForServices" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueIssuedForServices_416255" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueIssuedForServices_416255" order="5" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsAndOptionsDescription" xlink:label="loc_karxWarrantsAndOptionsDescription_97ef61" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxWarrantsAndOptionsDescription_97ef61" order="6" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MaintenanceAgreementDescription" xlink:label="loc_karxMaintenanceAgreementDescription_b85ce0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxMaintenanceAgreementDescription_b85ce0" order="7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DerivativeLiabilitiesMeasuredAtFairValueGain" xlink:label="loc_karxDerivativeLiabilitiesMeasuredAtFairValueGain_dcd4b5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxDerivativeLiabilitiesMeasuredAtFairValueGain_dcd4b5" order="8" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DerivativeLiabilityAtFairValueOtherChangesInFairValue" xlink:label="loc_karxDerivativeLiabilityAtFairValueOtherChangesInFairValue_49c11f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxDerivativeLiabilityAtFairValueOtherChangesInFairValue_49c11f" order="9" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DerivativeLiabilitiesDerivativesIssued" xlink:label="loc_karxDerivativeLiabilitiesDerivativesIssued_30579b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxDerivativeLiabilitiesDerivativesIssued_30579b" order="10" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsIssued" xlink:label="loc_karxWarrantsIssued_714db8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxWarrantsIssued_714db8" order="11" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ChangeInAccountingEstimateAndIncreasedDerivativeLiability" xlink:label="loc_karxChangeInAccountingEstimateAndIncreasedDerivativeLiability_80c75c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxChangeInAccountingEstimateAndIncreasedDerivativeLiability_80c75c" order="12" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DerivativeLiability" xlink:label="loc_karxDerivativeLiability_a7cda6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_karxDerivativeLiability_a7cda6" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaapAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_4b0acf" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9b8de5" xlink:to="loc_us-gaapAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_4b0acf" order="14" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/PrepaidExpensesDetails" xlink:title="995493 - Disclosure - Prepaid Expenses (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseCurrentAbstract" xlink:label="loc_us-gaapPrepaidExpenseCurrentAbstract_e12628" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PrepaidSponsorshipAndMarketingCurrent" xlink:label="loc_karxPrepaidSponsorshipAndMarketingCurrent_4bda6a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPrepaidExpenseCurrentAbstract_e12628" xlink:to="loc_karxPrepaidSponsorshipAndMarketingCurrent_4bda6a" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PrepaidBiocharEquipmentDepositCurrent" xlink:label="loc_karxPrepaidBiocharEquipmentDepositCurrent_817212" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPrepaidExpenseCurrentAbstract_e12628" xlink:to="loc_karxPrepaidBiocharEquipmentDepositCurrent_817212" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherPrepaidExpenseCurrent" xlink:label="loc_us-gaapOtherPrepaidExpenseCurrent_97b1e2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPrepaidExpenseCurrentAbstract_e12628" xlink:to="loc_us-gaapOtherPrepaidExpenseCurrent_97b1e2" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="loc_us-gaapPrepaidExpenseCurrent_3ee3c4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPrepaidExpenseCurrentAbstract_e12628" xlink:to="loc_us-gaapPrepaidExpenseCurrent_3ee3c4" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InventoryDetails" xlink:title="995494 - Disclosure - Inventory (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaapInventoryDisclosureAbstract_7e3f27" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CarbonCreditInventoryAmount" xlink:label="loc_karxCarbonCreditInventoryAmount_883d68" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInventoryDisclosureAbstract_7e3f27" xlink:to="loc_karxCarbonCreditInventoryAmount_883d68" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet_84369a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInventoryDisclosureAbstract_7e3f27" xlink:to="loc_us-gaapInventoryNet_84369a" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/PropertyAndEquipmentDetails" xlink:title="995495 - Disclosure - Property and Equipment (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PropertyAndEquipmentAbstract" xlink:label="loc_karxPropertyAndEquipmentAbstract_21d4eb" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FurnitureAndFixturesGross" xlink:label="loc_us-gaapFurnitureAndFixturesGross_62c40e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_21d4eb" xlink:to="loc_us-gaapFurnitureAndFixturesGross_62c40e" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedComputerSoftwareGross" xlink:label="loc_us-gaapCapitalizedComputerSoftwareGross_3d2e2d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_21d4eb" xlink:to="loc_us-gaapCapitalizedComputerSoftwareGross_3d2e2d" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaapPropertyPlantAndEquipmentGross_98fd4e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_21d4eb" xlink:to="loc_us-gaapPropertyPlantAndEquipmentGross_98fd4e" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_915d98" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_21d4eb" xlink:to="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_915d98" order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet_7dba11" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_21d4eb" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet_7dba11" order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/PropertyAndEquipmentDetailsNarrative" xlink:title="995496 - Disclosure - Property and Equipment (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PropertyAndEquipmentAbstract" xlink:label="loc_karxPropertyAndEquipmentAbstract_8f0001" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentAdditions" xlink:label="loc_us-gaapPropertyPlantAndEquipmentAdditions_71eb83" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_8f0001" xlink:to="loc_us-gaapPropertyPlantAndEquipmentAdditions_71eb83" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization" xlink:label="loc_us-gaapDepreciationAndAmortization_a77e4e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_8f0001" xlink:to="loc_us-gaapDepreciationAndAmortization_a77e4e" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Depreciation" xlink:label="loc_us-gaapDepreciation_a183bb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxPropertyAndEquipmentAbstract_8f0001" xlink:to="loc_us-gaapDepreciation_a183bb" order="3" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/AcquiredProjectPipelineDetails" xlink:title="995497 - Disclosure - Acquired Project Pipeline (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AcquiredProjectPipelineAbstract" xlink:label="loc_karxAcquiredProjectPipelineAbstract_98c27f" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProjectPipelineGross" xlink:label="loc_karxProjectPipelineGross_5bd2f5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_98c27f" xlink:to="loc_karxProjectPipelineGross_5bd2f5" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AccumulatedAmortizationOfPipelineCost" xlink:label="loc_karxAccumulatedAmortizationOfPipelineCost_f4cf25" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_98c27f" xlink:to="loc_karxAccumulatedAmortizationOfPipelineCost_f4cf25" order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaapIntangibleAssetsNetExcludingGoodwill_6e6cfe" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_98c27f" xlink:to="loc_us-gaapIntangibleAssetsNetExcludingGoodwill_6e6cfe" order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/AcquiredProjectPipelineDetailsNarrative" xlink:title="995498 - Disclosure - Acquired Project Pipeline (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AcquiredProjectPipelineAbstract" xlink:label="loc_karxAcquiredProjectPipelineAbstract_63b3bb" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AmortizationExpenseProjectPipeline" xlink:label="loc_karxAmortizationExpenseProjectPipeline_0e50c1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_63b3bb" xlink:to="loc_karxAmortizationExpenseProjectPipeline_0e50c1" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FiniteLivedIntangibleAssetsAmortizationExpensesNextTwelveMonths" xlink:label="loc_karxFiniteLivedIntangibleAssetsAmortizationExpensesNextTwelveMonths_92d9a1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_63b3bb" xlink:to="loc_karxFiniteLivedIntangibleAssetsAmortizationExpensesNextTwelveMonths_92d9a1" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:label="loc_us-gaapAcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_2c0383" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxAcquiredProjectPipelineAbstract_63b3bb" xlink:to="loc_us-gaapAcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_2c0383" order="3" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ContractFulfillmentAssetsDetails" xlink:title="995499 - Disclosure - Contract Fulfillment Assets (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ContractFulfillmentAssetsAbstract" xlink:label="loc_karxContractFulfillmentAssetsAbstract_00f003" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_9df916" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxContractFulfillmentAssetsAbstract_00f003" xlink:to="loc_us-gaapStatementTable_9df916" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_54f13b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_9df916" xlink:to="loc_us-gaapStatementLineItems_54f13b" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis_97d516" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_9df916" xlink:to="loc_us-gaapRelatedPartyTransactionAxis_97d516" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_a865b9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionAxis_97d516" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_a865b9" order="1020" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ABCMangroveSenegaMember" xlink:label="loc_karxABCMangroveSenegaMember_0ee276" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionDomain_a865b9" xlink:to="loc_karxABCMangroveSenegaMember_0ee276" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostNet" xlink:label="loc_us-gaapCapitalizedContractCostNet_b9f8e4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_54f13b" xlink:to="loc_us-gaapCapitalizedContractCostNet_b9f8e4" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerDetails" xlink:title="995500 - Disclosure - Other Assets, Maintenance Agreement and Consideration Payable to a Customer (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract" xlink:label="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_f4f9f3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MaintenanceAgreementRelatedToConsiderationPayableToACustomer" xlink:label="loc_karxMaintenanceAgreementRelatedToConsiderationPayableToACustomer_acf3d6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_f4f9f3" xlink:to="loc_karxMaintenanceAgreementRelatedToConsiderationPayableToACustomer_acf3d6" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredOfferingCosts" xlink:label="loc_us-gaapDeferredOfferingCosts_2e85e8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_f4f9f3" xlink:to="loc_us-gaapDeferredOfferingCosts_2e85e8" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecurityDeposit" xlink:label="loc_us-gaapSecurityDeposit_be04da" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_f4f9f3" xlink:to="loc_us-gaapSecurityDeposit_be04da" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DueFromOtherRelatedParty" xlink:label="loc_karxDueFromOtherRelatedParty_629c2d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_f4f9f3" xlink:to="loc_karxDueFromOtherRelatedParty_629c2d" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaapOtherAssetsNoncurrent_cfaafe" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_f4f9f3" xlink:to="loc_us-gaapOtherAssetsNoncurrent_cfaafe" order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerDetailNarrative" xlink:title="995501 - Disclosure - Other Assets, Maintenance Agreement and Consideration Payable to a Customer (Detail Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract" xlink:label="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_ee101e" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_d69b79" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherAssetsMaintenanceAgreementAndConsiderationPayableToACustomerAbstract_ee101e" xlink:to="loc_us-gaapStatementTable_d69b79" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_a5fd1d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_d69b79" xlink:to="loc_us-gaapStatementLineItems_a5fd1d" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_7fcfac" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_d69b79" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_7fcfac" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_cf45ca" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_7fcfac" xlink:to="loc_us-gaapRelatedPartyDomain_cf45ca" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis_3d4f2d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_d69b79" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis_3d4f2d" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_35f02e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis_3d4f2d" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_35f02e" order="1030" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MaintenanceAgreementMember" xlink:label="loc_karxMaintenanceAgreementMember_71e03c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_cf45ca" xlink:to="loc_karxMaintenanceAgreementMember_71e03c" order="1031" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerContractsMember" xlink:label="loc_us-gaapCustomerContractsMember_79bebd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_35f02e" xlink:to="loc_us-gaapCustomerContractsMember_79bebd" order="1032" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnamortizedDebtIssuanceExpense" xlink:label="loc_us-gaapUnamortizedDebtIssuanceExpense_0e611c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_a5fd1d" xlink:to="loc_us-gaapUnamortizedDebtIssuanceExpense_0e611c" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredIncomeRevenueRecognized" xlink:label="loc_us-gaapDeferredIncomeRevenueRecognized_377d56" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_a5fd1d" xlink:to="loc_us-gaapDeferredIncomeRevenueRecognized_377d56" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsCurrent" xlink:label="loc_us-gaapOtherAssetsCurrent_d335a3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_a5fd1d" xlink:to="loc_us-gaapOtherAssetsCurrent_d335a3" order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNet" xlink:label="loc_us-gaapContractWithCustomerAssetNet_16dbeb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_a5fd1d" xlink:to="loc_us-gaapContractWithCustomerAssetNet_16dbeb" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayable" xlink:label="loc_us-gaapConvertibleNotesPayable_cec649" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_a5fd1d" xlink:to="loc_us-gaapConvertibleNotesPayable_cec649" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssets" xlink:label="loc_us-gaapOtherAssets_1a24ab" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_a5fd1d" xlink:to="loc_us-gaapOtherAssets_1a24ab" order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LoanReceivableDetailNarrative" xlink:title="995502 - Disclosure - Loan Receivable (Detail Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LoanReceivableAbstract" xlink:label="loc_karxLoanReceivableAbstract_0bbb70" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_3d8724" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxLoanReceivableAbstract_0bbb70" xlink:to="loc_us-gaapStatementTable_3d8724" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_1b8fbc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_3d8724" xlink:to="loc_us-gaapStatementLineItems_1b8fbc" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis_568534" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_3d8724" xlink:to="loc_us-gaapPlanNameAxis_568534" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_deb883" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameAxis_568534" xlink:to="loc_us-gaapPlanNameDomain_deb883" order="1010" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LoanAgreementMember" xlink:label="loc_karxLoanAgreementMember_f151ba" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_deb883" xlink:to="loc_karxLoanAgreementMember_f151ba" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConversionGainsAndLossesOnForeignInvestments" xlink:label="loc_us-gaapConversionGainsAndLossesOnForeignInvestments_c8e68a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_us-gaapConversionGainsAndLossesOnForeignInvestments_c8e68a" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_InterestIncome" xlink:label="loc_karxInterestIncome_b887c6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxInterestIncome_b887c6" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="loc_us-gaapReceivablesNetCurrent_fe8af9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_us-gaapReceivablesNetCurrent_fe8af9" order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancingReceivableCoveredAfterAllowanceForCreditLoss" xlink:label="loc_us-gaapFinancingReceivableCoveredAfterAllowanceForCreditLoss_286217" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_us-gaapFinancingReceivableCoveredAfterAllowanceForCreditLoss_286217" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleNotesReceivable" xlink:label="loc_karxConvertibleNotesReceivable_4a4dce" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxConvertibleNotesReceivable_4a4dce" order="5" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleNotesReceivableIncludingAccruedInterest" xlink:label="loc_karxConvertibleNotesReceivableIncludingAccruedInterest_b88a4f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxConvertibleNotesReceivableIncludingAccruedInterest_b88a4f" order="6" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ExpectedIncreaseInAllowance" xlink:label="loc_karxExpectedIncreaseInAllowance_9317d9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxExpectedIncreaseInAllowance_9317d9" order="7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AdvancedToRelatedParty" xlink:label="loc_karxAdvancedToRelatedParty_72f233" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxAdvancedToRelatedParty_72f233" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="loc_us-gaapDebtInstrumentInterestRateEffectivePercentage_42839d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_us-gaapDebtInstrumentInterestRateEffectivePercentage_42839d" order="9" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_NumberOfSharesPledgedAsCollateral" xlink:label="loc_karxNumberOfSharesPledgedAsCollateral_83a357" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxNumberOfSharesPledgedAsCollateral_83a357" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestReceivable" xlink:label="loc_us-gaapInterestReceivable_0ffa61" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_us-gaapInterestReceivable_0ffa61" order="11" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IncreaseInAllowancesForCreditLosses" xlink:label="loc_karxIncreaseInAllowancesForCreditLosses_6b8cb8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxIncreaseInAllowancesForCreditLosses_6b8cb8" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllowanceForLoanAndLeaseLossesAdjustmentsNet" xlink:label="loc_us-gaapAllowanceForLoanAndLeaseLossesAdjustmentsNet_94a2f1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_us-gaapAllowanceForLoanAndLeaseLossesAdjustmentsNet_94a2f1" order="13" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IncreasesOfOtherOwnershipInterestsValue" xlink:label="loc_karxIncreasesOfOtherOwnershipInterestsValue_5c5f4a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1b8fbc" xlink:to="loc_karxIncreasesOfOtherOwnershipInterestsValue_5c5f4a" order="14" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/DeferredRevenueDetails" xlink:title="995503 - Disclosure - Deferred Revenue (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueAbstract" xlink:label="loc_us-gaapDeferredRevenueAbstract_638450" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueAndCredits" xlink:label="loc_us-gaapDeferredRevenueAndCredits_5c7b7f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_638450" xlink:to="loc_us-gaapDeferredRevenueAndCredits_5c7b7f" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DevelopmentCostPrepaymentsReceived" xlink:label="loc_karxDevelopmentCostPrepaymentsReceived_4eeded" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_638450" xlink:to="loc_karxDevelopmentCostPrepaymentsReceived_4eeded" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherCustomerPrepayments" xlink:label="loc_karxOtherCustomerPrepayments_a0f242" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_638450" xlink:to="loc_karxOtherCustomerPrepayments_a0f242" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ContractLiabilityAdvisoryServicesAdvance" xlink:label="loc_karxContractLiabilityAdvisoryServicesAdvance_98a55a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_638450" xlink:to="loc_karxContractLiabilityAdvisoryServicesAdvance_98a55a" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DeferredRentIncomeRelatedParty" xlink:label="loc_karxDeferredRentIncomeRelatedParty_da2527" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_638450" xlink:to="loc_karxDeferredRentIncomeRelatedParty_da2527" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaapDeferredRevenueCurrent_b4af28" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_638450" xlink:to="loc_us-gaapDeferredRevenueCurrent_b4af28" order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/DeferredRevenueDetailsNarrative" xlink:title="995504 - Disclosure - Deferred Revenue (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueAbstract" xlink:label="loc_us-gaapDeferredRevenueAbstract_1c5c9a" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_f806c4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDeferredRevenueAbstract_1c5c9a" xlink:to="loc_us-gaapStatementTable_f806c4" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_28f94d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_f806c4" xlink:to="loc_us-gaapStatementLineItems_28f94d" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis_267cda" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_f806c4" xlink:to="loc_us-gaapPlanNameAxis_267cda" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_77f524" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameAxis_267cda" xlink:to="loc_us-gaapPlanNameDomain_77f524" order="1010" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IRECSalesAgreementMember" xlink:label="loc_karxIRECSalesAgreementMember_baacb9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_77f524" xlink:to="loc_karxIRECSalesAgreementMember_baacb9" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfAnnuitiesAndInvestmentCertificates" xlink:label="loc_us-gaapRepaymentsOfAnnuitiesAndInvestmentCertificates_8c35e9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_28f94d" xlink:to="loc_us-gaapRepaymentsOfAnnuitiesAndInvestmentCertificates_8c35e9" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireRestrictedCertificatesOfDeposit" xlink:label="loc_us-gaapPaymentsToAcquireRestrictedCertificatesOfDeposit_13ea26" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_28f94d" xlink:to="loc_us-gaapPaymentsToAcquireRestrictedCertificatesOfDeposit_13ea26" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_NumberOfCertificatesForWhichPaymentReceived" xlink:label="loc_karxNumberOfCertificatesForWhichPaymentReceived_00c7b2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_28f94d" xlink:to="loc_karxNumberOfCertificatesForWhichPaymentReceived_00c7b2" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProceedsFromCustomersInDeferredRevenue" xlink:label="loc_karxProceedsFromCustomersInDeferredRevenue_6ac08c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_28f94d" xlink:to="loc_karxProceedsFromCustomersInDeferredRevenue_6ac08c" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DevelopmentCostsPrepaymentsReceived" xlink:label="loc_karxDevelopmentCostsPrepaymentsReceived_e9822a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_28f94d" xlink:to="loc_karxDevelopmentCostsPrepaymentsReceived_e9822a" order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaapDeferredRevenueCurrent_32408d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_28f94d" xlink:to="loc_us-gaapDeferredRevenueCurrent_32408d" order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherCurrentLiabilitiesDetails" xlink:title="995505 - Disclosure - Other Current Liabilities (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherCurrentLiabilitiesAbstract" xlink:label="loc_karxOtherCurrentLiabilitiesAbstract_106bca" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermBankLoansAndNotesPayable" xlink:label="loc_us-gaapShortTermBankLoansAndNotesPayable_8ee7d2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_106bca" xlink:to="loc_us-gaapShortTermBankLoansAndNotesPayable_8ee7d2" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="loc_us-gaapEmployeeRelatedLiabilitiesCurrent_6f9974" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_106bca" xlink:to="loc_us-gaapEmployeeRelatedLiabilitiesCurrent_6f9974" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalesAndExciseTaxPayableCurrent" xlink:label="loc_us-gaapSalesAndExciseTaxPayableCurrent_a46ae6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_106bca" xlink:to="loc_us-gaapSalesAndExciseTaxPayableCurrent_a46ae6" order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_GoodsReceivedNotInvoiced" xlink:label="loc_karxGoodsReceivedNotInvoiced_683d87" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_106bca" xlink:to="loc_karxGoodsReceivedNotInvoiced_683d87" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherAccruedLiabilitiesCurrentAndNoncurrentDuringPeriod" xlink:label="loc_karxOtherAccruedLiabilitiesCurrentAndNoncurrentDuringPeriod_5bdf14" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_106bca" xlink:to="loc_karxOtherAccruedLiabilitiesCurrentAndNoncurrentDuringPeriod_5bdf14" order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaapOtherLiabilitiesCurrent_8c4051" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_106bca" xlink:to="loc_us-gaapOtherLiabilitiesCurrent_8c4051" order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/OtherCurrentLiabilitiesDetailsNarrative" xlink:title="995506 - Disclosure - Other Current Liabilities (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherCurrentLiabilitiesAbstract" xlink:label="loc_karxOtherCurrentLiabilitiesAbstract_f57061" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_0b8666" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxOtherCurrentLiabilitiesAbstract_f57061" xlink:to="loc_us-gaapStatementTable_0b8666" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_82c5fe" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_0b8666" xlink:to="loc_us-gaapStatementLineItems_82c5fe" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis_50a429" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_0b8666" xlink:to="loc_us-gaapRelatedPartyTransactionAxis_50a429" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_b96c5b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionAxis_50a429" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_b96c5b" order="1010" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_KarbonXCorpMember" xlink:label="loc_karxKarbonXCorpMember_c7ed86" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionDomain_b96c5b" xlink:to="loc_karxKarbonXCorpMember_c7ed86" order="1011" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DueFromRelatedPartyCurrent" xlink:label="loc_karxDueFromRelatedPartyCurrent_b0d158" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_82c5fe" xlink:to="loc_karxDueFromRelatedPartyCurrent_b0d158" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ConvertibleNotesDetails" xlink:title="995507 - Disclosure - Convertible Notes (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleDebtAbstract" xlink:label="loc_karxConvertibleDebtAbstract_909ef4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_b21bb6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxConvertibleDebtAbstract_909ef4" xlink:to="loc_us-gaapStatementTable_b21bb6" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_f051a1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_b21bb6" xlink:to="loc_us-gaapStatementLineItems_f051a1" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_13cfbd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_b21bb6" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_13cfbd" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10d2d1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_13cfbd" xlink:to="loc_us-gaapRelatedPartyDomain_10d2d1" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingAxis" xlink:label="loc_us-gaapVestingAxis_acc0ab" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_b21bb6" xlink:to="loc_us-gaapVestingAxis_acc0ab" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain" xlink:label="loc_us-gaapVestingDomain_8294f2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapVestingAxis_acc0ab" xlink:to="loc_us-gaapVestingDomain_8294f2" order="1030" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OtherLendersMember" xlink:label="loc_karxOtherLendersMember_350832" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxOtherLendersMember_350832" order="1031" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OneLenderMember" xlink:label="loc_karxOneLenderMember_c3e8fe" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxOneLenderMember_c3e8fe" order="1032" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TheLenderMember" xlink:label="loc_karxTheLenderMember_135be5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxTheLenderMember_135be5" order="1033" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MaintenanceNoteMember" xlink:label="loc_karxMaintenanceNoteMember_f7db3b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapVestingDomain_8294f2" xlink:to="loc_karxMaintenanceNoteMember_f7db3b" order="1034" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DebtfundLPMember" xlink:label="loc_karxDebtfundLPMember_1417cb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxDebtfundLPMember_1417cb" order="1035" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember" xlink:label="loc_us-gaapShareBasedCompensationAwardTrancheOneMember_e30d08" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapVestingDomain_8294f2" xlink:to="loc_us-gaapShareBasedCompensationAwardTrancheOneMember_e30d08" order="1036" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheTwoMember" xlink:label="loc_us-gaapShareBasedCompensationAwardTrancheTwoMember_111614" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapVestingDomain_8294f2" xlink:to="loc_us-gaapShareBasedCompensationAwardTrancheTwoMember_111614" order="1037" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CFICapitalMember" xlink:label="loc_karxCFICapitalMember_8c73a6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxCFICapitalMember_8c73a6" order="1038" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_GWCapitalMember" xlink:label="loc_karxGWCapitalMember_635955" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxGWCapitalMember_635955" order="1039" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AuctusFundMember" xlink:label="loc_karxAuctusFundMember_cda0fa" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxAuctusFundMember_cda0fa" order="1040" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SilverCrestHybridCapitalMember" xlink:label="loc_karxSilverCrestHybridCapitalMember_6bc2f9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_10d2d1" xlink:to="loc_karxSilverCrestHybridCapitalMember_6bc2f9" order="1041" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaapDebtInstrumentCarryingAmount_628375" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_f051a1" xlink:to="loc_us-gaapDebtInstrumentCarryingAmount_628375" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentUnamortizedDiscount" xlink:label="loc_us-gaapDebtInstrumentUnamortizedDiscount_fd7063" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_f051a1" xlink:to="loc_us-gaapDebtInstrumentUnamortizedDiscount_fd7063" order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleLongTermNotesPayable" xlink:label="loc_us-gaapConvertibleLongTermNotesPayable_2cf442" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_f051a1" xlink:to="loc_us-gaapConvertibleLongTermNotesPayable_2cf442" order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableCurrent" xlink:label="loc_us-gaapConvertibleNotesPayableCurrent_3d9982" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_f051a1" xlink:to="loc_us-gaapConvertibleNotesPayableCurrent_3d9982" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ConvertibleNotesDetailsNarrative" xlink:title="995508 - Disclosure - Convertible Notes (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertibleDebtAbstract" xlink:label="loc_karxConvertibleDebtAbstract_f33530" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_30c264" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxConvertibleDebtAbstract_f33530" xlink:to="loc_us-gaapStatementTable_30c264" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_e9cb2c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_30c264" xlink:to="loc_us-gaapStatementLineItems_e9cb2c" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeAxis" xlink:label="loc_us-gaapShortTermDebtTypeAxis_e37f53" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_30c264" xlink:to="loc_us-gaapShortTermDebtTypeAxis_e37f53" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain_5c5e37" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShortTermDebtTypeAxis_e37f53" xlink:to="loc_us-gaapShortTermDebtTypeDomain_5c5e37" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis_6382a3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_30c264" xlink:to="loc_us-gaapPlanNameAxis_6382a3" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_c16491" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameAxis_6382a3" xlink:to="loc_us-gaapPlanNameDomain_c16491" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_f35361" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_30c264" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_f35361" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_36f63e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_f35361" xlink:to="loc_us-gaapRelatedPartyDomain_36f63e" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis_ac49d4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_30c264" xlink:to="loc_us-gaapStatementClassOfStockAxis_ac49d4" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_29a2dd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementClassOfStockAxis_ac49d4" xlink:to="loc_us-gaapClassOfStockDomain_29a2dd" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis_edef31" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_30c264" xlink:to="loc_us-gaapRelatedPartyTransactionAxis_edef31" order="1070" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_11920c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionAxis_edef31" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_11920c" order="1070" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableMember" xlink:label="loc_us-gaapConvertibleNotesPayableMember_dcee9d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShortTermDebtTypeDomain_5c5e37" xlink:to="loc_us-gaapConvertibleNotesPayableMember_dcee9d" order="1071" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_BottomMember" xlink:label="loc_karxBottomMember_9875eb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_c16491" xlink:to="loc_karxBottomMember_9875eb" order="1072" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MaintenanceAgreementMember" xlink:label="loc_karxMaintenanceAgreementMember_b4f6ac" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_36f63e" xlink:to="loc_karxMaintenanceAgreementMember_b4f6ac" order="1073" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TopMember" xlink:label="loc_karxTopMember_37afb4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_c16491" xlink:to="loc_karxTopMember_37afb4" order="1074" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertiblePromissoryNotesFiveMember" xlink:label="loc_karxConvertiblePromissoryNotesFiveMember_f92cd1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapClassOfStockDomain_29a2dd" xlink:to="loc_karxConvertiblePromissoryNotesFiveMember_f92cd1" order="1075" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FiveConvertibleNotesPayableMember" xlink:label="loc_karxFiveConvertibleNotesPayableMember_4c6709" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShortTermDebtTypeDomain_5c5e37" xlink:to="loc_karxFiveConvertibleNotesPayableMember_4c6709" order="1076" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FiveLendersMember" xlink:label="loc_karxFiveLendersMember_be8e36" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionDomain_11920c" xlink:to="loc_karxFiveLendersMember_be8e36" order="1077" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AmortizationOfDebtDiscount" xlink:label="loc_karxAmortizationOfDebtDiscount_f48fc8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_karxAmortizationOfDebtDiscount_f48fc8" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaapDebtInstrumentCarryingAmount_543427" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapDebtInstrumentCarryingAmount_543427" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentUnamortizedDiscount" xlink:label="loc_us-gaapDebtInstrumentUnamortizedDiscount_95fe53" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapDebtInstrumentUnamortizedDiscount_95fe53" order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPayableCurrent" xlink:label="loc_us-gaapInterestPayableCurrent_18d0e0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapInterestPayableCurrent_18d0e0" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability" xlink:label="loc_us-gaapEmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability_902e46" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapEmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability_902e46" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayable" xlink:label="loc_us-gaapConvertibleNotesPayable_fb9c1c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapConvertibleNotesPayable_fb9c1c" order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionDescription" xlink:label="loc_us-gaapDebtConversionDescription_26377d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapDebtConversionDescription_26377d" order="7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AggregatePurchasePrices" xlink:label="loc_karxAggregatePurchasePrices_443c99" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_karxAggregatePurchasePrices_443c99" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueOfAssetsAcquired" xlink:label="loc_us-gaapFairValueOfAssetsAcquired_be7202" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapFairValueOfAssetsAcquired_be7202" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnSaleOfDerivatives" xlink:label="loc_us-gaapGainLossOnSaleOfDerivatives_1481e2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapGainLossOnSaleOfDerivatives_1481e2" order="10" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DiscountOnDebt" xlink:label="loc_karxDiscountOnDebt_ba82de" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_karxDiscountOnDebt_ba82de" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionConvertedInstrumentRate" xlink:label="loc_us-gaapDebtConversionConvertedInstrumentRate_67d670" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_us-gaapDebtConversionConvertedInstrumentRate_67d670" order="12" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_BeneficialOwnershipLimitationsRate" xlink:label="loc_karxBeneficialOwnershipLimitationsRate_590555" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_e9cb2c" xlink:to="loc_karxBeneficialOwnershipLimitationsRate_590555" order="13" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LongTermDebtDetails" xlink:title="995509 - Disclosure - Long-Term Debt (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtAbstract" xlink:label="loc_us-gaapLongTermDebtAbstract_2bb4e4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaapDebtInstrumentFaceAmount_52f702" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLongTermDebtAbstract_2bb4e4" xlink:to="loc_us-gaapDebtInstrumentFaceAmount_52f702" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_UnamortizedDebtDiscountAndIssuanceCosts" xlink:label="loc_karxUnamortizedDebtDiscountAndIssuanceCosts_146ea6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLongTermDebtAbstract_2bb4e4" xlink:to="loc_karxUnamortizedDebtDiscountAndIssuanceCosts_146ea6" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaapLongTermDebtNoncurrent_a1e300" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLongTermDebtAbstract_2bb4e4" xlink:to="loc_us-gaapLongTermDebtNoncurrent_a1e300" order="3" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LongTermDebtDetailsNarrative" xlink:title="995510 - Disclosure - Long-Term Debt (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtAbstract" xlink:label="loc_us-gaapLongTermDebtAbstract_966178" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_279b13" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapLongTermDebtAbstract_966178" xlink:to="loc_us-gaapStatementTable_279b13" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_0157e8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_279b13" xlink:to="loc_us-gaapStatementLineItems_0157e8" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis_354000" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_279b13" xlink:to="loc_us-gaapRelatedPartyTransactionAxis_354000" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_28d95a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionAxis_354000" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_28d95a" order="1010" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LenderMember" xlink:label="loc_karxLenderMember_855903" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionDomain_28d95a" xlink:to="loc_karxLenderMember_855903" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaapDebtInstrumentFaceAmount_b18844" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_us-gaapDebtInstrumentFaceAmount_b18844" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaapDebtInstrumentInterestRateStatedPercentage_ec5ffd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_us-gaapDebtInstrumentInterestRateStatedPercentage_ec5ffd" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_InterestPaidDuringQuarter" xlink:label="loc_karxInterestPaidDuringQuarter_af6d26" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_karxInterestPaidDuringQuarter_af6d26" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AmountWithheldAtClosing" xlink:label="loc_karxAmountWithheldAtClosing_a29315" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_karxAmountWithheldAtClosing_a29315" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ScheduledMonthlyPrincipalAmortizationAmount" xlink:label="loc_karxScheduledMonthlyPrincipalAmortizationAmount_708cee" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_karxScheduledMonthlyPrincipalAmortizationAmount_708cee" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive" xlink:label="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive_140ef5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive_140ef5" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfDebtDiscountPremium" xlink:label="loc_us-gaapAmortizationOfDebtDiscountPremium_3e7b0d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_us-gaapAmortizationOfDebtDiscountPremium_3e7b0d" order="7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_UnamortizationDebtDiscount" xlink:label="loc_karxUnamortizationDebtDiscount_b4b9ad" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_0157e8" xlink:to="loc_karxUnamortizationDebtDiscount_b4b9ad" order="8" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoanDetails" xlink:title="995511 - Disclosure - Receivables Financing Obligations and Term Loan (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReceivablesFinancingObligationsAbstract" xlink:label="loc_karxReceivablesFinancingObligationsAbstract_2f3ecd" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_8123ad" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxReceivablesFinancingObligationsAbstract_2f3ecd" xlink:to="loc_us-gaapStatementTable_8123ad" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_96cd82" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_8123ad" xlink:to="loc_us-gaapStatementLineItems_96cd82" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MajorCustomersAxis" xlink:label="loc_srtMajorCustomersAxis_09740e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_8123ad" xlink:to="loc_srtMajorCustomersAxis_09740e" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srtNameOfMajorCustomerDomain_58e08b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtMajorCustomersAxis_09740e" xlink:to="loc_srtNameOfMajorCustomerDomain_58e08b" order="1020" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProviderAMember" xlink:label="loc_karxProviderAMember_270802" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtNameOfMajorCustomerDomain_58e08b" xlink:to="loc_karxProviderAMember_270802" order="1021" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProviderBMember" xlink:label="loc_karxProviderBMember_2be4e9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtNameOfMajorCustomerDomain_58e08b" xlink:to="loc_karxProviderBMember_2be4e9" order="1022" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TermLoanPayableMember" xlink:label="loc_karxTermLoanPayableMember_0a57d2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtNameOfMajorCustomerDomain_58e08b" xlink:to="loc_karxTermLoanPayableMember_0a57d2" order="1023" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProviderCMember" xlink:label="loc_karxProviderCMember_7650a8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtNameOfMajorCustomerDomain_58e08b" xlink:to="loc_karxProviderCMember_7650a8" order="1024" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProviderDMember" xlink:label="loc_karxProviderDMember_b5a7b0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtNameOfMajorCustomerDomain_58e08b" xlink:to="loc_karxProviderDMember_b5a7b0" order="1025" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReceivablesFinancingObligations" xlink:label="loc_karxReceivablesFinancingObligations_bc0d08" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_96cd82" xlink:to="loc_karxReceivablesFinancingObligations_bc0d08" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TotalReceivablesFinancingObligationsAndTermLoan" xlink:label="loc_karxTotalReceivablesFinancingObligationsAndTermLoan_850524" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_96cd82" xlink:to="loc_karxTotalReceivablesFinancingObligationsAndTermLoan_850524" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TermLoanPayablePresentedSeparately" xlink:label="loc_karxTermLoanPayablePresentedSeparately_1a481a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_96cd82" xlink:to="loc_karxTermLoanPayablePresentedSeparately_1a481a" order="3" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ReceivablesFinancingObligationsAndTermLoanDetailsNarrative" xlink:title="995512 - Disclosure - Receivables Financing Obligations and Term Loan (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReceivablesFinancingObligationsAbstract" xlink:label="loc_karxReceivablesFinancingObligationsAbstract_fdbd6a" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_f58709" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxReceivablesFinancingObligationsAbstract_fdbd6a" xlink:to="loc_us-gaapStatementTable_f58709" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_4cb7a7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_f58709" xlink:to="loc_us-gaapStatementLineItems_4cb7a7" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralAxis" xlink:label="loc_us-gaapCollateralAxis_443d03" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_f58709" xlink:to="loc_us-gaapCollateralAxis_443d03" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralDomain" xlink:label="loc_us-gaapCollateralDomain_f3458a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCollateralAxis_443d03" xlink:to="loc_us-gaapCollateralDomain_f3458a" order="1020" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AssetsPledgedAsCollateralMember" xlink:label="loc_karxAssetsPledgedAsCollateralMember_540392" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCollateralDomain_f3458a" xlink:to="loc_karxAssetsPledgedAsCollateralMember_540392" order="1021" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DescriptionOfTermLoan" xlink:label="loc_karxDescriptionOfTermLoan_6cf762" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_4cb7a7" xlink:to="loc_karxDescriptionOfTermLoan_6cf762" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FinancingObligationsOfMerchantDescription" xlink:label="loc_karxFinancingObligationsOfMerchantDescription_41dbee" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_4cb7a7" xlink:to="loc_karxFinancingObligationsOfMerchantDescription_41dbee" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet_737610" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_4cb7a7" xlink:to="loc_us-gaapInventoryNet_737610" order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Cash" xlink:label="loc_us-gaapCash_25ac05" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_4cb7a7" xlink:to="loc_us-gaapCash_25ac05" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNet" xlink:label="loc_us-gaapAccountsReceivableNet_32add1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_4cb7a7" xlink:to="loc_us-gaapAccountsReceivableNet_32add1" order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ShareholdersEquityDetailNarrative" xlink:title="995513 - Disclosure - Shareholders Equity (Detail Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareholdersEquityAbstract" xlink:label="loc_karxShareholdersEquityAbstract_d8ae6b" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesOther" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesOther_cafa5b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesOther_cafa5b" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueOther" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueOther_7b37e5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueOther_7b37e5" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued_f4f3c2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapCommonStockSharesIssued_f4f3c2" order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding_7d8be0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapCommonStockSharesOutstanding_7d8be0" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesShareBasedCompensation_674890" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesShareBasedCompensation_674890" order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensationGross" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueShareBasedCompensationGross_1a4e52" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueShareBasedCompensationGross_1a4e52" order="6" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_NumberOfSharesIssuedForSettlementOfFindersFeeShares" xlink:label="loc_karxNumberOfSharesIssuedForSettlementOfFindersFeeShares_4f2f92" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxNumberOfSharesIssuedForSettlementOfFindersFeeShares_4f2f92" order="7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_NumberOfSharesIssuedForSettlementOfFindersFeeAmount" xlink:label="loc_karxNumberOfSharesIssuedForSettlementOfFindersFeeAmount_020398" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxNumberOfSharesIssuedForSettlementOfFindersFeeAmount_020398" order="8" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_NumberOfCommitmentSharesIssuedShares" xlink:label="loc_karxNumberOfCommitmentSharesIssuedShares_8c96bd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxNumberOfCommitmentSharesIssuedShares_8c96bd" order="9" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_NumberOfCommitmentSharesIssuedAmount" xlink:label="loc_karxNumberOfCommitmentSharesIssuedAmount_47b14f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxNumberOfCommitmentSharesIssuedAmount_47b14f" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_6742a8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_6742a8" order="11" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockIssuedDuringPeriodValuesConversionOfConvertibleSecurities" xlink:label="loc_karxStockIssuedDuringPeriodValuesConversionOfConvertibleSecurities_35c0bb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxStockIssuedDuringPeriodValuesConversionOfConvertibleSecurities_35c0bb" order="12" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SharesIssuanceCost" xlink:label="loc_karxSharesIssuanceCost_a9933a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxSharesIssuanceCost_a9933a" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockOptionPlanExpense" xlink:label="loc_us-gaapStockOptionPlanExpense_aa9783" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_us-gaapStockOptionPlanExpense_aa9783" order="14" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IssuanceOfSharesUponConversionOfNotesPayableAndAccruedInterestAmount" xlink:label="loc_karxIssuanceOfSharesUponConversionOfNotesPayableAndAccruedInterestAmount_d7eb38" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxIssuanceOfSharesUponConversionOfNotesPayableAndAccruedInterestAmount_d7eb38" order="15" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IssuanceOfSharesUponConversionOfNotesPayableAndAccruedInterestShares" xlink:label="loc_karxIssuanceOfSharesUponConversionOfNotesPayableAndAccruedInterestShares_f6bf3d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxShareholdersEquityAbstract_d8ae6b" xlink:to="loc_karxIssuanceOfSharesUponConversionOfNotesPayableAndAccruedInterestShares_f6bf3d" order="16" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/WarrantsDetails" xlink:title="995514 - Disclosure - Warrants (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsAbstract" xlink:label="loc_karxWarrantsAbstract_643eba" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="loc_us-gaapClassOfWarrantOrRightOutstanding_3da26d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapClassOfWarrantOrRightOutstanding_3da26d" order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockIssuedDuringPeriodSharesStockOptionsGranted" xlink:label="loc_karxStockIssuedDuringPeriodSharesStockOptionsGranted_44f8ba" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_karxStockIssuedDuringPeriodSharesStockOptionsGranted_44f8ba" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesStockOptionsExercised_2da90a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesStockOptionsExercised_2da90a" order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_5a826d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_5a826d" order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="loc_us-gaapClassOfWarrantOrRightOutstanding_72f246" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapClassOfWarrantOrRightOutstanding_72f246" order="5" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_91a0c7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_91a0c7" order="6" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantedInPeriodWeightedAverageExercisePrice" xlink:label="loc_karxShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantedInPeriodWeightedAverageExercisePrice_b57566" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_karxShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantedInPeriodWeightedAverageExercisePrice_b57566" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_910345" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_910345" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_ed305a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_ed305a" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_e3b771" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_e3b771" order="10" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WeightedAverageRemainingContractualLifeInYearsBeginningBalance" xlink:label="loc_karxWeightedAverageRemainingContractualLifeInYearsBeginningBalance_40e8b3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_karxWeightedAverageRemainingContractualLifeInYearsBeginningBalance_40e8b3" order="11" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WeightedAverageRemainingContractualLifeInYearsEndingBalance" xlink:label="loc_karxWeightedAverageRemainingContractualLifeInYearsEndingBalance_f583bc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_643eba" xlink:to="loc_karxWeightedAverageRemainingContractualLifeInYearsEndingBalance_f583bc" order="12" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/WarrantsDetailsNarrative" xlink:title="995515 - Disclosure - Warrants (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsAbstract" xlink:label="loc_karxWarrantsAbstract_182abe" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_049f4e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxWarrantsAbstract_182abe" xlink:to="loc_us-gaapStatementTable_049f4e" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_84ae3f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_049f4e" xlink:to="loc_us-gaapStatementLineItems_84ae3f" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingAxis" xlink:label="loc_us-gaapVestingAxis_652da8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_049f4e" xlink:to="loc_us-gaapVestingAxis_652da8" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain" xlink:label="loc_us-gaapVestingDomain_11fa87" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapVestingAxis_652da8" xlink:to="loc_us-gaapVestingDomain_11fa87" order="1010" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MasterNoteTranche1January82026Member" xlink:label="loc_karxMasterNoteTranche1January82026Member_fc7a92" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapVestingDomain_11fa87" xlink:to="loc_karxMasterNoteTranche1January82026Member_fc7a92" order="1011" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MasterNoteTranche2February182026Member" xlink:label="loc_karxMasterNoteTranche2February182026Member_02267a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapVestingDomain_11fa87" xlink:to="loc_karxMasterNoteTranche2February182026Member_02267a" order="1012" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarantsDescriptionOfBlackScholes" xlink:label="loc_karxWarantsDescriptionOfBlackScholes_1b6ae5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_karxWarantsDescriptionOfBlackScholes_1b6ae5" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_d70d92" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_d70d92" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaapSharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageRemainingContractualTerm2_aa6038" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_us-gaapSharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageRemainingContractualTerm2_aa6038" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareBasedCompensationsArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_karxShareBasedCompensationsArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_fca812" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_karxShareBasedCompensationsArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_fca812" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ClosingPriceOfCommonStock" xlink:label="loc_karxClosingPriceOfCommonStock_b28c1c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_karxClosingPriceOfCommonStock_b28c1c" order="5" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CommonStockPurchaseWarrantsIssued" xlink:label="loc_karxCommonStockPurchaseWarrantsIssued_196d83" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_karxCommonStockPurchaseWarrantsIssued_196d83" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="loc_us-gaapClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_11a1f9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_us-gaapClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_11a1f9" order="7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_BeneficialOwnershipLimitationsRate" xlink:label="loc_karxBeneficialOwnershipLimitationsRate_cb407d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_karxBeneficialOwnershipLimitationsRate_cb407d" order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_FairValueAtIssuanceOfWarrant" xlink:label="loc_karxFairValueAtIssuanceOfWarrant_4052bc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_84ae3f" xlink:to="loc_karxFairValueAtIssuanceOfWarrant_4052bc" order="9" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InvestmentsAndSecuritiesReceivableDetails" xlink:title="995516 - Disclosure - Investments and Securities Receivable (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentsAbstract" xlink:label="loc_us-gaapInvestmentsAbstract_5e8b6b" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityMethodInvestments" xlink:label="loc_us-gaapEquityMethodInvestments_885930" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_5e8b6b" xlink:to="loc_us-gaapEquityMethodInvestments_885930" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherReceivables" xlink:label="loc_us-gaapOtherReceivables_c092cc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_5e8b6b" xlink:to="loc_us-gaapOtherReceivables_c092cc" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Investments" xlink:label="loc_us-gaapInvestments_b78f54" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_5e8b6b" xlink:to="loc_us-gaapInvestments_b78f54" order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InvestmentsAndSecuritiesReceivableDetailsNarrative" xlink:title="995517 - Disclosure - Investments and Securities Receivable (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentsAbstract" xlink:label="loc_us-gaapInvestmentsAbstract_64bb2b" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesPurchaseOfAssets" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesPurchaseOfAssets_1abad4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_64bb2b" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesPurchaseOfAssets_1abad4" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecuritiesPurchasedUnderAgreementsToResellDecrease" xlink:label="loc_us-gaapSecuritiesPurchasedUnderAgreementsToResellDecrease_ea5692" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_64bb2b" xlink:to="loc_us-gaapSecuritiesPurchasedUnderAgreementsToResellDecrease_ea5692" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SecuritiesDescriptionOfReceivables" xlink:label="loc_karxSecuritiesDescriptionOfReceivables_70a2bf" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_64bb2b" xlink:to="loc_karxSecuritiesDescriptionOfReceivables_70a2bf" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PriceRiskDerivativeLiabilitiesAtFairValue" xlink:label="loc_us-gaapPriceRiskDerivativeLiabilitiesAtFairValue_2c45b5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_64bb2b" xlink:to="loc_us-gaapPriceRiskDerivativeLiabilitiesAtFairValue_2c45b5" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RemainingSecuritiesSettlement" xlink:label="loc_karxRemainingSecuritiesSettlement_e2ff78" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapInvestmentsAbstract_64bb2b" xlink:to="loc_karxRemainingSecuritiesSettlement_e2ff78" order="5" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/InternallyDevelopedSoftwareDetailsNarrative" xlink:title="995518 - Disclosure - Internally Developed Software (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_InternallyDevelopedSoftwareAbstract" xlink:label="loc_karxInternallyDevelopedSoftwareAbstract_d8dae3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TradingSecuritiesDebtAmortizedCost" xlink:label="loc_us-gaapTradingSecuritiesDebtAmortizedCost_018930" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxInternallyDevelopedSoftwareAbstract_d8dae3" xlink:to="loc_us-gaapTradingSecuritiesDebtAmortizedCost_018930" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaapAmortizationOfIntangibleAssets_f630a1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxInternallyDevelopedSoftwareAbstract_d8dae3" xlink:to="loc_us-gaapAmortizationOfIntangibleAssets_f630a1" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedAmortizationOfOtherDeferredCosts" xlink:label="loc_us-gaapAccumulatedAmortizationOfOtherDeferredCosts_8cf9d7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxInternallyDevelopedSoftwareAbstract_d8dae3" xlink:to="loc_us-gaapAccumulatedAmortizationOfOtherDeferredCosts_8cf9d7" order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedComputerSoftwareNet" xlink:label="loc_us-gaapCapitalizedComputerSoftwareNet_3dff7d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxInternallyDevelopedSoftwareAbstract_d8dae3" xlink:to="loc_us-gaapCapitalizedComputerSoftwareNet_3dff7d" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestCostsCapitalized" xlink:label="loc_us-gaapInterestCostsCapitalized_004ce3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxInternallyDevelopedSoftwareAbstract_d8dae3" xlink:to="loc_us-gaapInterestCostsCapitalized_004ce3" order="5" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/StockOptionPlanDetails" xlink:title="995519 - Disclosure - Stock Option Plan (Details)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockOptionPlanAbstract" xlink:label="loc_karxStockOptionPlanAbstract_f433bd" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_27bd8d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxStockOptionPlanAbstract_f433bd" xlink:to="loc_us-gaapStatementTable_27bd8d" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_9dcd18" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_27bd8d" xlink:to="loc_us-gaapStatementLineItems_9dcd18" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaapDerivativeInstrumentRiskAxis_4666f7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_27bd8d" xlink:to="loc_us-gaapDerivativeInstrumentRiskAxis_4666f7" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaapDerivativeContractTypeDomain_965178" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDerivativeInstrumentRiskAxis_4666f7" xlink:to="loc_us-gaapDerivativeContractTypeDomain_965178" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockOptionMember" xlink:label="loc_us-gaapStockOptionMember_2f6c49" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapDerivativeContractTypeDomain_965178" xlink:to="loc_us-gaapStockOptionMember_2f6c49" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_45e32c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_45e32c" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_8f9d0d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_8f9d0d" order="2" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_ab8586" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_ab8586" order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesStockOptionsExercised_a50825" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesStockOptionsExercised_a50825" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_47ba1b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_47ba1b" order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_387776" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_387776" order="6" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_7c6d14" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_7c6d14" order="7" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_16aeeb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_16aeeb" order="8" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares" xlink:label="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_69dada" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_69dada" order="9" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_85c88b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_85c88b" order="10" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_cec1e3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_cec1e3" order="11" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_96397c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_96397c" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_0226de" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_0226de" order="13" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_689b0d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_689b0d" order="14" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WeightedAverageExercisePriceOptionsExercisable" xlink:label="loc_karxWeightedAverageExercisePriceOptionsExercisable_c80aa8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_karxWeightedAverageExercisePriceOptionsExercisable_c80aa8" order="15" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvested" xlink:label="loc_karxShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvested_8ba393" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_karxShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvested_8ba393" order="16" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm" xlink:label="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm_656e25" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm_656e25" order="17" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermExercisable" xlink:label="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermExercisable_190799" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermExercisable_190799" order="18" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermUnvested" xlink:label="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermUnvested_c57b09" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermUnvested_c57b09" order="19" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermGranted" xlink:label="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermGranted_a67ac1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermGranted_a67ac1" order="20" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2Ending" xlink:label="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2Ending_710e99" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_9dcd18" xlink:to="loc_karxSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2Ending_710e99" order="21" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/StockOptionPlanDetailNarrative" xlink:title="995520 - Disclosure - Stock Option Plan (Detail Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockOptionPlanAbstract" xlink:label="loc_karxStockOptionPlanAbstract_dd7626" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_0ec042" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxStockOptionPlanAbstract_dd7626" xlink:to="loc_us-gaapStatementTable_0ec042" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_73cc8e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_0ec042" xlink:to="loc_us-gaapStatementLineItems_73cc8e" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis_0e5d76" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_0ec042" xlink:to="loc_us-gaapPlanNameAxis_0e5d76" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_ccd310" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameAxis_0e5d76" xlink:to="loc_us-gaapPlanNameDomain_ccd310" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srtTitleOfIndividualAxis_feeed5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_0ec042" xlink:to="loc_srtTitleOfIndividualAxis_feeed5" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_37d357" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtTitleOfIndividualAxis_feeed5" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_37d357" order="1030" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_EmployeesDirectorsOfficersAndConsultantsStockOptionPlanMember" xlink:label="loc_karxEmployeesDirectorsOfficersAndConsultantsStockOptionPlanMember_1ee43a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_ccd310" xlink:to="loc_karxEmployeesDirectorsOfficersAndConsultantsStockOptionPlanMember_1ee43a" order="1031" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockBasedCompensationExpenseMember" xlink:label="loc_karxStockBasedCompensationExpenseMember_c91695" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_ccd310" xlink:to="loc_karxStockBasedCompensationExpenseMember_c91695" order="1032" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_BoardOfDirectorsChairmanMember" xlink:label="loc_srtBoardOfDirectorsChairmanMember_f41b05" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_37d357" xlink:to="loc_srtBoardOfDirectorsChairmanMember_f41b05" order="1033" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesGranted" xlink:label="loc_karxShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesGranted_3798b4" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesGranted_3798b4" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="loc_us-gaapClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_6fdc88" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_6fdc88" order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares" xlink:label="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_69a911" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_69a911" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_b759ef" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_b759ef" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="loc_us-gaapSaleOfStockPricePerShare_bb76bf" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapSaleOfStockPricePerShare_bb76bf" order="5" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IncrementalOnFairValue" xlink:label="loc_karxIncrementalOnFairValue_3af647" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxIncrementalOnFairValue_3af647" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_2859fc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_2859fc" order="7" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_6ee722" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_6ee722" order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGrantDate" xlink:label="loc_karxShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGrantDate_5ad839" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGrantDate_5ad839" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_674966" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_674966" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_6c90d0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_6c90d0" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:label="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_0d3346" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_0d3346" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_e744b9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_e744b9" order="13" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_StockOptionPlanDescription" xlink:label="loc_karxStockOptionPlanDescription_c7182e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxStockOptionPlanDescription_c7182e" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaapAllocatedShareBasedCompensationExpense_22abc7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapAllocatedShareBasedCompensationExpense_22abc7" order="15" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ShareBasedCompensationOnSharesIssuedForServices" xlink:label="loc_karxShareBasedCompensationOnSharesIssuedForServices_918b54" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxShareBasedCompensationOnSharesIssuedForServices_918b54" order="16" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_UnvestedStockOptionsPlan" xlink:label="loc_karxUnvestedStockOptionsPlan_e92067" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxUnvestedStockOptionsPlan_e92067" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_5a0157" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_5a0157" order="18" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AggregateIntrinsicSharesOutstanding" xlink:label="loc_karxAggregateIntrinsicSharesOutstanding_b10281" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxAggregateIntrinsicSharesOutstanding_b10281" order="19" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ClosingMarketPriceOfCommonStock" xlink:label="loc_karxClosingMarketPriceOfCommonStock_42b8ef" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_73cc8e" xlink:to="loc_karxClosingMarketPriceOfCommonStock_42b8ef" order="20" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/IncomeTaxesDetailNarrative" xlink:title="995521 - Disclosure - Income Taxes (Detail Narrative)">
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_IncomeTaxesAbstract" xlink:label="loc_karxIncomeTaxesAbstract_c6666a" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:label="loc_us-gaapEffectiveIncomeTaxRateContinuingOperations_2d7498" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_karxIncomeTaxesAbstract_c6666a" xlink:to="loc_us-gaapEffectiveIncomeTaxRateContinuingOperations_2d7498" order="1" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LossPerShareDetails" xlink:title="995522 - Disclosure - Loss Per Share (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaapEarningsPerShareAbstract_6dd170" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_fb9c7f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEarningsPerShareAbstract_6dd170" xlink:to="loc_us-gaapStatementTable_fb9c7f" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_055f6a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_fb9c7f" xlink:to="loc_us-gaapStatementLineItems_055f6a" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaapAwardTypeAxis_a6a478" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_fb9c7f" xlink:to="loc_us-gaapAwardTypeAxis_a6a478" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_6e275b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAwardTypeAxis_a6a478" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_6e275b" order="1020" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertiblenotesConvertedMember" xlink:label="loc_karxConvertiblenotesConvertedMember_9f4490" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_6e275b" xlink:to="loc_karxConvertiblenotesConvertedMember_9f4490" order="1021" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OptionsMember" xlink:label="loc_karxOptionsMember_abc187" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_6e275b" xlink:to="loc_karxOptionsMember_abc187" order="1022" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantsMember" xlink:label="loc_karxWarrantsMember_5fbea9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_6e275b" xlink:to="loc_karxWarrantsMember_5fbea9" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaapAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_8b0667" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_055f6a" xlink:to="loc_us-gaapAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_8b0667" order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/LossPerShareDetailsNarrative" xlink:title="995523 - Disclosure - Loss Per Share (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaapEarningsPerShareAbstract_2132cf" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_150849" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapEarningsPerShareAbstract_2132cf" xlink:to="loc_us-gaapStatementTable_150849" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_1d01b6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_150849" xlink:to="loc_us-gaapStatementLineItems_1d01b6" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis_3c46d2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_150849" xlink:to="loc_us-gaapPlanNameAxis_3c46d2" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_946839" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameAxis_3c46d2" xlink:to="loc_us-gaapPlanNameDomain_946839" order="1010" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TopMember" xlink:label="loc_karxTopMember_8d5dbe" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_946839" xlink:to="loc_karxTopMember_8d5dbe" order="1011" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_BottomMember" xlink:label="loc_karxBottomMember_8d0a4b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_946839" xlink:to="loc_karxBottomMember_8d0a4b" order="1012" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaapWeightedAverageNumberOfSharesOutstandingBasic_f1d4d3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1d01b6" xlink:to="loc_us-gaapWeightedAverageNumberOfSharesOutstandingBasic_f1d4d3" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfUnits_665fc3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1d01b6" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfUnits_665fc3" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaapEarningsPerShareBasic_802bcd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1d01b6" xlink:to="loc_us-gaapEarningsPerShareBasic_802bcd" order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:label="loc_us-gaapDebtInstrumentConvertibleConversionPrice1_ecafba" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_1d01b6" xlink:to="loc_us-gaapDebtInstrumentConvertibleConversionPrice1_ecafba" order="4" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/RelatedPartyTransactionsDetailsNarrative" xlink:title="995524 - Disclosure - Related Party Transactions (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="loc_us-gaapRelatedPartyTransactionsAbstract_d3bfc0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_69b5f0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionsAbstract_d3bfc0" xlink:to="loc_us-gaapStatementTable_69b5f0" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_3e3490" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_69b5f0" xlink:to="loc_us-gaapStatementLineItems_3e3490" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srtTitleOfIndividualAxis_73a21e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_69b5f0" xlink:to="loc_srtTitleOfIndividualAxis_73a21e" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_5c227a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtTitleOfIndividualAxis_73a21e" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_5c227a" order="1010" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MrClovisMember" xlink:label="loc_karxMrClovisMember_5efa08" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_5c227a" xlink:to="loc_karxMrClovisMember_5efa08" order="1011" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RelatedPartyTransactionsDescription" xlink:label="loc_karxRelatedPartyTransactionsDescription_b9d815" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_3e3490" xlink:to="loc_karxRelatedPartyTransactionsDescription_b9d815" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ProceedsFromConvertibleDebtNote" xlink:label="loc_karxProceedsFromConvertibleDebtNote_c3d66a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_3e3490" xlink:to="loc_karxProceedsFromConvertibleDebtNote_c3d66a" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OfficersCompensation" xlink:label="loc_us-gaapOfficersCompensation_dbc417" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_3e3490" xlink:to="loc_us-gaapOfficersCompensation_dbc417" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedInvestmentIncomeReceivable" xlink:label="loc_us-gaapAccruedInvestmentIncomeReceivable_c577ed" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_3e3490" xlink:to="loc_us-gaapAccruedInvestmentIncomeReceivable_c577ed" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalesTypeLeaseLeaseReceivable" xlink:label="loc_us-gaapSalesTypeLeaseLeaseReceivable_3dc926" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_3e3490" xlink:to="loc_us-gaapSalesTypeLeaseLeaseReceivable_3dc926" order="5" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/ConcentrationsDetailsNarrative" xlink:title="995525 - Disclosure - Concentrations (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RisksAndUncertaintiesAbstract" xlink:label="loc_us-gaapRisksAndUncertaintiesAbstract_2b60af" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_79a564" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRisksAndUncertaintiesAbstract_2b60af" xlink:to="loc_us-gaapStatementTable_79a564" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_38a0cc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_79a564" xlink:to="loc_us-gaapStatementLineItems_38a0cc" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis_27d967" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_79a564" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis_27d967" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_3fcb80" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis_27d967" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_3fcb80" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis" xlink:label="loc_us-gaapAccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_fb47ba" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_79a564" xlink:to="loc_us-gaapAccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_fb47ba" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReceivableTypeDomain" xlink:label="loc_us-gaapReceivableTypeDomain_f9e1ff" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapAccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_fb47ba" xlink:to="loc_us-gaapReceivableTypeDomain_f9e1ff" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis_030a39" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_79a564" xlink:to="loc_us-gaapRelatedPartyTransactionAxis_030a39" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_9837f7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionAxis_030a39" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_9837f7" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerContractsMember" xlink:label="loc_us-gaapCustomerContractsMember_22cdac" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_3fcb80" xlink:to="loc_us-gaapCustomerContractsMember_22cdac" order="1041" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TradeAccountsReceivableMember" xlink:label="loc_us-gaapTradeAccountsReceivableMember_33296f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapReceivableTypeDomain_f9e1ff" xlink:to="loc_us-gaapTradeAccountsReceivableMember_33296f" order="1042" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_KarbonXTradingMember" xlink:label="loc_karxKarbonXTradingMember_5ce0aa" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionDomain_9837f7" xlink:to="loc_karxKarbonXTradingMember_5ce0aa" order="1043" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RevenueConcentrationPercentage" xlink:label="loc_karxRevenueConcentrationPercentage_65a1cc" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_38a0cc" xlink:to="loc_karxRevenueConcentrationPercentage_65a1cc" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConcentrationRiskPercentage" xlink:label="loc_karxConcentrationRiskPercentage_ec393a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_38a0cc" xlink:to="loc_karxConcentrationRiskPercentage_ec393a" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_dfb36c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_38a0cc" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_dfb36c" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent_af4bf8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_38a0cc" xlink:to="loc_us-gaapAccountsReceivableNetCurrent_af4bf8" order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CommitmentsAndContingenciesDetails" xlink:title="995526 - Disclosure - Commitments and Contingencies (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_c637c8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_c637c8" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearTwo_9c6d5d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearTwo_9c6d5d" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearThree_ffbb4b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearThree_ffbb4b" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearFour_50355d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearFour_50355d" order="4" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" xlink:label="loc_karxLesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_6dcb4e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_karxLesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_6dcb4e" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDue_a6248a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDue_a6248a" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityUndiscountedExcessAmount_95f9ad" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityUndiscountedExcessAmount_95f9ad" order="7" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiability" xlink:label="loc_us-gaapOperatingLeaseLiability_11df72" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapOperatingLeaseLiability_11df72" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityCurrent_868a4f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapOperatingLeaseLiabilityCurrent_868a4f" order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityNoncurrent_adb80f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapOperatingLeaseLiabilityNoncurrent_adb80f" order="10" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:label="loc_us-gaapOperatingLeaseWeightedAverageDiscountRatePercent_88a132" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_us-gaapOperatingLeaseWeightedAverageDiscountRatePercent_88a132" order="11" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OperatingLeaseWeightedAverageRemainingLeaseTerm" xlink:label="loc_karxOperatingLeaseWeightedAverageRemainingLeaseTerm_15e1de" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_ea2bbf" xlink:to="loc_karxOperatingLeaseWeightedAverageRemainingLeaseTerm_15e1de" order="12" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:title="995527 - Disclosure - Commitments and Contingencies (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_60f2d7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LeaseAndRentalExpenses" xlink:label="loc_karxLeaseAndRentalExpenses_ecba74" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_60f2d7" xlink:to="loc_karxLeaseAndRentalExpenses_ecba74" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DescriptionOfLeaseTerm" xlink:label="loc_karxDescriptionOfLeaseTerm_9d969d" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_60f2d7" xlink:to="loc_karxDescriptionOfLeaseTerm_9d969d" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LesseeOperatingLeaseTermOfContracts" xlink:label="loc_karxLesseeOperatingLeaseTermOfContracts_543f9b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_60f2d7" xlink:to="loc_karxLesseeOperatingLeaseTermOfContracts_543f9b" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OperatingLeasesDescription" xlink:label="loc_karxOperatingLeasesDescription_7b0911" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract_60f2d7" xlink:to="loc_karxOperatingLeasesDescription_7b0911" order="4" />
  </link:presentationLink>
  <link:presentationLink xlink:type="extended" xlink:role="http://karx.com/role/SubsequentEventsDetailsNarrative" xlink:title="995528 - Disclosure - Subsequent Events (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaapSubsequentEventsAbstract_356a7f" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable_bda02e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapSubsequentEventsAbstract_356a7f" xlink:to="loc_us-gaapStatementTable_bda02e" order="100" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems_012f37" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_bda02e" xlink:to="loc_us-gaapStatementLineItems_012f37" order="2000" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaapSubsequentEventTypeAxis_7533dd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_bda02e" xlink:to="loc_us-gaapSubsequentEventTypeAxis_7533dd" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaapSubsequentEventTypeDomain_e546a8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapSubsequentEventTypeAxis_7533dd" xlink:to="loc_us-gaapSubsequentEventTypeDomain_e546a8" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeAxis" xlink:label="loc_us-gaapShortTermDebtTypeAxis_50a2a1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_bda02e" xlink:to="loc_us-gaapShortTermDebtTypeAxis_50a2a1" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain_60dcba" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShortTermDebtTypeAxis_50a2a1" xlink:to="loc_us-gaapShortTermDebtTypeDomain_60dcba" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis_540bb3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_bda02e" xlink:to="loc_us-gaapPlanNameAxis_540bb3" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_42295c" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameAxis_540bb3" xlink:to="loc_us-gaapPlanNameDomain_42295c" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srtTitleOfIndividualAxis_5d17b5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_bda02e" xlink:to="loc_srtTitleOfIndividualAxis_5d17b5" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_ec3a1f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtTitleOfIndividualAxis_5d17b5" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_ec3a1f" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_b22080" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementTable_bda02e" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_b22080" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_2d801a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_b22080" xlink:to="loc_us-gaapRelatedPartyDomain_2d801a" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaapSubsequentEventMember_4ba7c1" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapSubsequentEventTypeDomain_e546a8" xlink:to="loc_us-gaapSubsequentEventMember_4ba7c1" order="1061" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConversionsOfConvertibleNotesMember" xlink:label="loc_karxConversionsOfConvertibleNotesMember_ff781e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapShortTermDebtTypeDomain_60dcba" xlink:to="loc_karxConversionsOfConvertibleNotesMember_ff781e" order="1062" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TopMember" xlink:label="loc_karxTopMember_c864a9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_42295c" xlink:to="loc_karxTopMember_c864a9" order="1063" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_BottomMember" xlink:label="loc_karxBottomMember_7914b5" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_42295c" xlink:to="loc_karxBottomMember_7914b5" order="1064" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ReceivablesFinancingMember" xlink:label="loc_karxReceivablesFinancingMember_7c2ffe" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_42295c" xlink:to="loc_karxReceivablesFinancingMember_7c2ffe" order="1065" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConversionsAndShareIssuancesMember" xlink:label="loc_karxConversionsAndShareIssuancesMember_1d77b8" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapPlanNameDomain_42295c" xlink:to="loc_karxConversionsAndShareIssuancesMember_1d77b8" order="1066" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_BoardOfDirectorsChairmanMember" xlink:label="loc_srtBoardOfDirectorsChairmanMember_6cd2ee" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_ec3a1f" xlink:to="loc_srtBoardOfDirectorsChairmanMember_6cd2ee" order="1067" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConsultingAgreementsMember" xlink:label="loc_karxConsultingAgreementsMember_ab4caa" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapRelatedPartyDomain_2d801a" xlink:to="loc_karxConsultingAgreementsMember_ab4caa" order="1068" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CarbonCreditsPurchaseShares" xlink:label="loc_karxCarbonCreditsPurchaseShares_a5a565" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCarbonCreditsPurchaseShares_a5a565" order="1" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_AdvertisingAndPromotionalAgreementDescription" xlink:label="loc_karxAdvertisingAndPromotionalAgreementDescription_38d5b7" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxAdvertisingAndPromotionalAgreementDescription_38d5b7" order="2" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_TradeFinancingDescription" xlink:label="loc_karxTradeFinancingDescription_2b72ee" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxTradeFinancingDescription_2b72ee" order="3" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CarbonCreditPurchaseAgreementDescription" xlink:label="loc_karxCarbonCreditPurchaseAgreementDescription_358c17" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCarbonCreditPurchaseAgreementDescription_358c17" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionConvertedInstrumentAmount1" xlink:label="loc_us-gaapDebtConversionConvertedInstrumentAmount1_ae6e4f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_us-gaapDebtConversionConvertedInstrumentAmount1_ae6e4f" order="5" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DebtInstrumentConvertibleConversionPrice15F" xlink:label="loc_karxDebtInstrumentConvertibleConversionPrice15F_fd2aae" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxDebtInstrumentConvertibleConversionPrice15F_fd2aae" order="6" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CommitmentSharesOfCommonStockIssued" xlink:label="loc_karxCommitmentSharesOfCommonStockIssued_ec6c78" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCommitmentSharesOfCommonStockIssued_ec6c78" order="7" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_WarrantToPurchaseShares" xlink:label="loc_karxWarrantToPurchaseShares_70f1d6" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxWarrantToPurchaseShares_70f1d6" order="8" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_OrganizationalCostExpenseBC" xlink:label="loc_karxOrganizationalCostExpenseBC_4d1e5f" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxOrganizationalCostExpenseBC_4d1e5f" order="9" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_PurchasedAmounts" xlink:label="loc_karxPurchasedAmounts_dd42b0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxPurchasedAmounts_dd42b0" order="10" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RepayableWeeklyRemittancesAmount" xlink:label="loc_karxRepayableWeeklyRemittancesAmount_8ba453" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxRepayableWeeklyRemittancesAmount_8ba453" order="11" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CashFee" xlink:label="loc_karxCashFee_6f7414" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCashFee_6f7414" order="12" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CashFeeInstalmentsAmount" xlink:label="loc_karxCashFeeInstalmentsAmount_4cd5fd" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCashFeeInstalmentsAmount_4cd5fd" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesRestrictedStock" xlink:label="loc_us-gaapWeightedAverageNumberOfSharesRestrictedStock_d25558" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_us-gaapWeightedAverageNumberOfSharesRestrictedStock_d25558" order="14" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubordinatedBorrowingInterestRate" xlink:label="loc_us-gaapSubordinatedBorrowingInterestRate_24bef3" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_us-gaapSubordinatedBorrowingInterestRate_24bef3" order="15" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:label="loc_us-gaapDebtInstrumentConvertibleConversionPrice1_97432b" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_us-gaapDebtInstrumentConvertibleConversionPrice1_97432b" order="16" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_RestrictedSharesOfCommonStock" xlink:label="loc_karxRestrictedSharesOfCommonStock_5c931e" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxRestrictedSharesOfCommonStock_5c931e" order="17" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_MarketingServicesAgreementShares" xlink:label="loc_karxMarketingServicesAgreementShares_d10bc2" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxMarketingServicesAgreementShares_d10bc2" order="18" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CommonStockIssuedAndOutstanding" xlink:label="loc_karxCommonStockIssuedAndOutstanding_66f469" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCommonStockIssuedAndOutstanding_66f469" order="19" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionOriginalDebtAmount1" xlink:label="loc_us-gaapDebtConversionOriginalDebtAmount1_6b63ad" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_us-gaapDebtConversionOriginalDebtAmount1_6b63ad" order="20" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CashProceedsAfterCosts" xlink:label="loc_karxCashProceedsAfterCosts_14ddeb" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCashProceedsAfterCosts_14ddeb" order="21" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_ConvertiblePromissoryNotesPrincipalAmount" xlink:label="loc_karxConvertiblePromissoryNotesPrincipalAmount_cdc2f9" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxConvertiblePromissoryNotesPrincipalAmount_cdc2f9" order="22" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentIncreaseAccruedInterest" xlink:label="loc_us-gaapDebtInstrumentIncreaseAccruedInterest_10d60a" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_us-gaapDebtInstrumentIncreaseAccruedInterest_10d60a" order="23" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_LegalServices" xlink:label="loc_karxLegalServices_2cab37" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxLegalServices_2cab37" order="24" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_CommitmentSharesInConnectionWithConvertibleNote" xlink:label="loc_karxCommitmentSharesInConnectionWithConvertibleNote_388375" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxCommitmentSharesInConnectionWithConvertibleNote_388375" order="25" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="loc_us-gaapSaleOfStockPricePerShare_053775" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_us-gaapSaleOfStockPricePerShare_053775" order="26" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
    <link:loc xlink:type="locator" xlink:href="karx-20260831.xsd#karx_DiscountToMarketPrice" xlink:label="loc_karxDiscountToMarketPrice_402fb0" />
    <link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaapStatementLineItems_012f37" xlink:to="loc_karxDiscountToMarketPrice_402fb0" order="27" />
  </link:presentationLink>
</link:linkbase>
