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<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel"/>
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  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel"/>
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_ck0000880268_C000144193Member_label_en-US" xlink:label="lab_ck0000880268_C000144193Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000144193 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000144193Member_documentation_en-US" xlink:label="lab_ck0000880268_C000144193Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000144193 - R Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000144193Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000144193Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000144193Member" xlink:to="lab_ck0000880268_C000144193Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentTypeCategorizationMember_label_en-US" xlink:label="lab_us-gaap_InvestmentTypeCategorizationMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investments [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember" xlink:to="lab_us-gaap_InvestmentTypeCategorizationMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_ConvertiblePreferredSecuritiesMember_label_en-US" xlink:label="lab_ck0000880268_ConvertiblePreferredSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Convertible Preferred Securities [Member]</link:label>
    <link:label id="lab_ck0000880268_ConvertiblePreferredSecuritiesMember_documentation_en-US" xlink:label="lab_ck0000880268_ConvertiblePreferredSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Convertible Preferred Securities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_ConvertiblePreferredSecuritiesMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_ConvertiblePreferredSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_ConvertiblePreferredSecuritiesMember" xlink:to="lab_ck0000880268_ConvertiblePreferredSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000109548Member_label_en-US" xlink:label="lab_ck0000880268_C000109548Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000109548 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000109548Member_documentation_en-US" xlink:label="lab_ck0000880268_C000109548Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000109548 - Global Bond C Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000109548Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000109548Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000109548Member" xlink:to="lab_ck0000880268_C000109548Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000109546Member_label_en-US" xlink:label="lab_ck0000880268_C000109546Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000109546 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000109546Member_documentation_en-US" xlink:label="lab_ck0000880268_C000109546Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000109546 - Global Bond R5 Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000109546Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000109546Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000109546Member" xlink:to="lab_ck0000880268_C000109546Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CorporateBondSecuritiesMember_label_en-US" xlink:label="lab_us-gaap_CorporateBondSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Corporate Bond Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateBondSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateBondSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CorporateBondSecuritiesMember" xlink:to="lab_us-gaap_CorporateBondSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000189710Member_label_en-US" xlink:label="lab_ck0000880268_C000189710Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000189710 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000189710Member_documentation_en-US" xlink:label="lab_ck0000880268_C000189710Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000189710 - Global Bond I Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000189710Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000189710Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000189710Member" xlink:to="lab_ck0000880268_C000189710Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000189714Member_label_en-US" xlink:label="lab_ck0000880268_C000189714Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000189714 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000189714Member_documentation_en-US" xlink:label="lab_ck0000880268_C000189714Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000189714 - Y Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000189714Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000189714Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000189714Member" xlink:to="lab_ck0000880268_C000189714Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000144190Member_label_en-US" xlink:label="lab_ck0000880268_C000144190Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000144190 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000144190Member_documentation_en-US" xlink:label="lab_ck0000880268_C000144190Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000144190 - R5</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000144190Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000144190Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000144190Member" xlink:to="lab_ck0000880268_C000144190Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_MunicipalSecuritiesMember_label_en-US" xlink:label="lab_ck0000880268_MunicipalSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Municipal Securities [Member]</link:label>
    <link:label id="lab_ck0000880268_MunicipalSecuritiesMember_documentation_en-US" xlink:label="lab_ck0000880268_MunicipalSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Municipal Securities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_MunicipalSecuritiesMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_MunicipalSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_MunicipalSecuritiesMember" xlink:to="lab_ck0000880268_MunicipalSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_OtherAssetsAndLiabilitiesMember_label_en-US" xlink:label="lab_ck0000880268_OtherAssetsAndLiabilitiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Assets and Liabilities [Member]</link:label>
    <link:label id="lab_ck0000880268_OtherAssetsAndLiabilitiesMember_documentation_en-US" xlink:label="lab_ck0000880268_OtherAssetsAndLiabilitiesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Assets and Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_OtherAssetsAndLiabilitiesMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_OtherAssetsAndLiabilitiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_OtherAssetsAndLiabilitiesMember" xlink:to="lab_ck0000880268_OtherAssetsAndLiabilitiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_PreferredSecuritiesMember_label_en-US" xlink:label="lab_ck0000880268_PreferredSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Securities [Member]</link:label>
    <link:label id="lab_ck0000880268_PreferredSecuritiesMember_documentation_en-US" xlink:label="lab_ck0000880268_PreferredSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Preferred Securities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_PreferredSecuritiesMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_PreferredSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_PreferredSecuritiesMember" xlink:to="lab_ck0000880268_PreferredSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000131612Member_label_en-US" xlink:label="lab_ck0000880268_C000131612Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000131612 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000131612Member_documentation_en-US" xlink:label="lab_ck0000880268_C000131612Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000131612 - Global Bond R6 Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000131612Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000131612Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000131612Member" xlink:to="lab_ck0000880268_C000131612Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_CollateralizedLoanObligationMember_label_en-US" xlink:label="lab_ck0000880268_CollateralizedLoanObligationMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Collateralized Loan Obligation [Member]</link:label>
    <link:label id="lab_ck0000880268_CollateralizedLoanObligationMember_documentation_en-US" xlink:label="lab_ck0000880268_CollateralizedLoanObligationMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Collateralized Loan Obligation</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_CollateralizedLoanObligationMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_CollateralizedLoanObligationMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_CollateralizedLoanObligationMember" xlink:to="lab_ck0000880268_CollateralizedLoanObligationMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000144192Member_label_en-US" xlink:label="lab_ck0000880268_C000144192Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000144192 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000144192Member_documentation_en-US" xlink:label="lab_ck0000880268_C000144192Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000144192 - C Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000144192Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000144192Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000144192Member" xlink:to="lab_ck0000880268_C000144192Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_U.S.TreasurySecuritiesMember_label_en-US" xlink:label="lab_ck0000880268_U.S.TreasurySecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">U.S. Treasury Securities [Member]</link:label>
    <link:label id="lab_ck0000880268_U.S.TreasurySecuritiesMember_documentation_en-US" xlink:label="lab_ck0000880268_U.S.TreasurySecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">U.S. Treasury Securities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_U.S.TreasurySecuritiesMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_U.S.TreasurySecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_U.S.TreasurySecuritiesMember" xlink:to="lab_ck0000880268_U.S.TreasurySecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_CommercialMortgageBackedSecurityMember_label_en-US" xlink:label="lab_ck0000880268_CommercialMortgageBackedSecurityMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Mortgage-Backed Security [Member]</link:label>
    <link:label id="lab_ck0000880268_CommercialMortgageBackedSecurityMember_documentation_en-US" xlink:label="lab_ck0000880268_CommercialMortgageBackedSecurityMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Mortgage-Backed Security</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_CommercialMortgageBackedSecurityMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_CommercialMortgageBackedSecurityMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_CommercialMortgageBackedSecurityMember" xlink:to="lab_ck0000880268_CommercialMortgageBackedSecurityMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000109545Member_label_en-US" xlink:label="lab_ck0000880268_C000109545Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000109545 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000109545Member_documentation_en-US" xlink:label="lab_ck0000880268_C000109545Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000109545 Global Bond - Investor Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000109545Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000109545Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000109545Member" xlink:to="lab_ck0000880268_C000109545Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000194400Member_label_en-US" xlink:label="lab_ck0000880268_C000194400Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000194400 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000194400Member_documentation_en-US" xlink:label="lab_ck0000880268_C000194400Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000194400 - Global Bond G Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000194400Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000194400Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000194400Member" xlink:to="lab_ck0000880268_C000194400Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CollateralizedMortgageObligationsMember_label_en-US" xlink:label="lab_us-gaap_CollateralizedMortgageObligationsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Collateralized Mortgage Obligations [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedMortgageObligationsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralizedMortgageObligationsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CollateralizedMortgageObligationsMember" xlink:to="lab_us-gaap_CollateralizedMortgageObligationsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000144189Member_label_en-US" xlink:label="lab_ck0000880268_C000144189Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000144189 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000144189Member_documentation_en-US" xlink:label="lab_ck0000880268_C000144189Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000144189</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000144189Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000144189Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000144189Member" xlink:to="lab_ck0000880268_C000144189Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000194401Member_label_en-US" xlink:label="lab_ck0000880268_C000194401Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000194401 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000194401Member_documentation_en-US" xlink:label="lab_ck0000880268_C000194401Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000194401 - G Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000194401Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000194401Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000194401Member" xlink:to="lab_ck0000880268_C000194401Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000189713Member_label_en-US" xlink:label="lab_ck0000880268_C000189713Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000189713 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000189713Member_documentation_en-US" xlink:label="lab_ck0000880268_C000189713Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000189713 - I Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000189713Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000189713Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000189713Member" xlink:to="lab_ck0000880268_C000189713Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_ShortTermInvestmentMember_label_en-US" xlink:label="lab_ck0000880268_ShortTermInvestmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Investment [Member]</link:label>
    <link:label id="lab_ck0000880268_ShortTermInvestmentMember_documentation_en-US" xlink:label="lab_ck0000880268_ShortTermInvestmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Investment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_ShortTermInvestmentMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_ShortTermInvestmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_ShortTermInvestmentMember" xlink:to="lab_ck0000880268_ShortTermInvestmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000144194Member_label_en-US" xlink:label="lab_ck0000880268_C000144194Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000144194 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000144194Member_documentation_en-US" xlink:label="lab_ck0000880268_C000144194Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000144194 - R6 Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000144194Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000144194Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000144194Member" xlink:to="lab_ck0000880268_C000144194Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000109547Member_label_en-US" xlink:label="lab_ck0000880268_C000109547Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000109547 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000109547Member_documentation_en-US" xlink:label="lab_ck0000880268_C000109547Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000109547 - Global Bond A Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000109547Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000109547Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000109547Member" xlink:to="lab_ck0000880268_C000109547Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember_label_en-US" xlink:label="lab_ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">U.S. Government Agency Mortgage-Backed Securities [Member]</link:label>
    <link:label id="lab_ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember_documentation_en-US" xlink:label="lab_ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">U.S. Government Agency Mortgage-Backed Securities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember" xlink:to="lab_ck0000880268_U.S.GovernmentAgencyMortgageBackedSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_SovereignGovernmentsAndAgenciesMember_label_en-US" xlink:label="lab_ck0000880268_SovereignGovernmentsAndAgenciesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sovereign Governments and Agencies [Member]</link:label>
    <link:label id="lab_ck0000880268_SovereignGovernmentsAndAgenciesMember_documentation_en-US" xlink:label="lab_ck0000880268_SovereignGovernmentsAndAgenciesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sovereign Governments and Agencies</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_SovereignGovernmentsAndAgenciesMember" xlink:href="ck0000880268-20260430.xsd#ck0000880268_SovereignGovernmentsAndAgenciesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_SovereignGovernmentsAndAgenciesMember" xlink:to="lab_ck0000880268_SovereignGovernmentsAndAgenciesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000109549Member_label_en-US" xlink:label="lab_ck0000880268_C000109549Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000109549 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000109549Member_documentation_en-US" xlink:label="lab_ck0000880268_C000109549Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000109549 - Global Bond R Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000109549Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000109549Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000109549Member" xlink:to="lab_ck0000880268_C000109549Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000144191Member_label_en-US" xlink:label="lab_ck0000880268_C000144191Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000144191 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000144191Member_documentation_en-US" xlink:label="lab_ck0000880268_C000144191Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000144191 - A Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000144191Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000144191Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000144191Member" xlink:to="lab_ck0000880268_C000144191Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AssetBackedSecuritiesMember_label_en-US" xlink:label="lab_us-gaap_AssetBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset-Backed Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetBackedSecuritiesMember" xlink:to="lab_us-gaap_AssetBackedSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000880268_C000189711Member_label_en-US" xlink:label="lab_ck0000880268_C000189711Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000189711 [Member]</link:label>
    <link:label id="lab_ck0000880268_C000189711Member_documentation_en-US" xlink:label="lab_ck0000880268_C000189711Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000189711 - Global Bond Y Class</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000880268_C000189711Member" xlink:href="ck0000880268-20260430.xsd#ck0000880268_C000189711Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000880268_C000189711Member" xlink:to="lab_ck0000880268_C000189711Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AssetsNet_label_en-US" xlink:label="lab_us-gaap_AssetsNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsNet" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsNet" xlink:to="lab_us-gaap_AssetsNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentCompanyPortfolioTurnover_label_en-US" xlink:label="lab_us-gaap_InvestmentCompanyPortfolioTurnover" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Company, Portfolio Turnover</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyPortfolioTurnover" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyPortfolioTurnover"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentCompanyPortfolioTurnover" xlink:to="lab_us-gaap_InvestmentCompanyPortfolioTurnover" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentTypeAxis_label_en-US" xlink:label="lab_us-gaap_InvestmentTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentTypeAxis" xlink:to="lab_us-gaap_InvestmentTypeAxis" xlink:type="arc" order="1"/>
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