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<!-- Generated by DFIN XBRL Schema Document - http://www.dfinsolutions.com/ - on 10-06-2026 12:30:12 PM -->
<!-- Copyright(c) 2026 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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	<import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
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	<import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd"/>   
	<import namespace="http://xbrl.sec.gov/country/2025" schemaLocation="https://xbrl.sec.gov/country/2025/country-2025.xsd"/>
	<import namespace="http://fasb.org/srt/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd"/>
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	<import namespace="http://xbrl.sec.gov/oef-sr/2025" schemaLocation="https://xbrl.sec.gov/oef/2025/oef-sr-2025.xsd"/>
	<import namespace="http://fasb.org/us-gaap/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd"/>
	<import namespace="http://fasb.org/us-roles/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd"/>
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				<link:roleRef roleURI="http://xbrl.sec.gov/oef/role/ShareholderReportHoldingsDetails" xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#ShareholderReportHoldingsDetails"/>
				<link:roleRef roleURI="http://xbrl.sec.gov/oef/role/ShareholderReportLineGraphDetails" xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#ShareholderReportLineGraphDetails"/>
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					<link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="IndustrySectorDomain" xlink:to="WTICrudeOilMember" order="6.0" />
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					<link:presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="IndustrySectorDomain" xlink:to="UnleadedGasolineMember" order="7.0" />
					<link:loc xlink:type="locator" xlink:href="#mstxv_SoybeansMember" xlink:label="SoybeansMember"/>
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					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="USGovernmentDebtSecuritiesMember" order="16.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FixedIncomeSecuritiesMember" xlink:label="FixedIncomeSecuritiesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="FixedIncomeSecuritiesMember" order="17.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CommodityExposureMember" xlink:label="CommodityExposureMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="CommodityExposureMember" order="18.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_FederalAgenciesMember" xlink:label="FederalAgenciesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="FederalAgenciesMember" order="19.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NonFixedIncomeMember" xlink:label="NonFixedIncomeMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="NonFixedIncomeMember" order="20.0"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/BroadBasedIndexOnly">               
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_BroadBasedIndexDomain" xlink:label="BroadBasedIndexDomain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/AdditionalIndexOnly">              
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_AdditionalIndexDomain" xlink:label="AdditionalIndexDomain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/MaturityOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_MaturityDomain" xlink:label="MaturityDomain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/IndustrySectorOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_IndustrySectorDomain" xlink:label="IndustrySectorDomain"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_HeatingOilMember" xlink:label="HeatingOilMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="HeatingOilMember" order="1.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NaturalGasReservesMember" xlink:label="NaturalGasReservesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="NaturalGasReservesMember" order="2.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_BrentCrudeMember" xlink:label="BrentCrudeMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="BrentCrudeMember" order="3.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_GoldSectorMember" xlink:label="GoldSectorMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="GoldSectorMember" order="4.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_WTICrudeOilMember" xlink:label="WTICrudeOilMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="WTICrudeOilMember" order="5.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_UnleadedGasolineMember" xlink:label="UnleadedGasolineMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="UnleadedGasolineMember" order="6.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SoybeansMember" xlink:label="SoybeansMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="SoybeansMember" order="7.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CornMember" xlink:label="CornMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="CornMember" order="8.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_LiveCattleMember" xlink:label="LiveCattleMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="LiveCattleMember" order="9.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CopperCOMEXMember" xlink:label="CopperCOMEXMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="CopperCOMEXMember" order="10.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_GasOilMember" xlink:label="GasOilMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="GasOilMember" order="11.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_AluminumMember" xlink:label="AluminumMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="AluminumMember" order="12.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SoybeanOilMember" xlink:label="SoybeanOilMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="SoybeanOilMember" order="13.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SilverMember" xlink:label="SilverMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="SilverMember" order="14.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NickelMember" xlink:label="NickelMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="NickelMember" order="15.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SoybeanMealMember" xlink:label="SoybeanMealMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="SoybeanMealMember" order="16.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_ZincMember" xlink:label="ZincMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="ZincMember" order="17.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CoffeeMember" xlink:label="CoffeeMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="CoffeeMember" order="18.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_LeanHogsMember" xlink:label="LeanHogsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="LeanHogsMember" order="19.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_FeederCattleMember" xlink:label="FeederCattleMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="FeederCattleMember" order="20.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_WheatMember" xlink:label="WheatMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="WheatMember" order="21.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SugarMember" xlink:label="SugarMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="SugarMember" order="22.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_PlatinumMember" xlink:label="PlatinumMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="PlatinumMember" order="23.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CocoaMember" xlink:label="CocoaMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="CocoaMember" order="24.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_KansasWheatMember" xlink:label="KansasWheatMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="KansasWheatMember" order="25.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CottonMember" xlink:label="CottonMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="CottonMember" order="26.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_LeadMember" xlink:label="LeadMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="LeadMember" order="27.0"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/CreditQualityOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_CreditQualityDomain" xlink:label="CreditQualityDomain"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NotRatedMember" xlink:label="NotRatedMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditQualityDomain" xlink:to="NotRatedMember" order="1.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CashAndCashEquivalentsQualityMember" xlink:label="CashAndCashEquivalentsQualityMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditQualityDomain" xlink:to="CashAndCashEquivalentsQualityMember" order="2.0"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_OtherMember" xlink:label="OtherMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditQualityDomain" xlink:to="OtherMember" order="3.0"/>
				</link:definitionLink>
				<!--GeographicRegionOnly use only for STPR-->
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/GeographicRegionOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_GeographicRegionDomain" xlink:label="GeographicRegionDomain"/>
				</link:definitionLink>
				<link:labelLink xlink:type="extended" xlink:role="http://www.xbrl.org/2003/role/link">               
					<link:loc xlink:type="locator" xlink:href="#mstxv_AsiaPacificExJapanEquityMember" xlink:label="AsiaPacificExJapanEquityMember"/>
					<link:label xlink:type="resource" xlink:label="label_AsiaPacificExJapanEquityMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Asia Pacific ex Japan Equity [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AsiaPacificExJapanEquityMember" xlink:to="label_AsiaPacificExJapanEquityMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_EmergingMarketsEquityMember" xlink:label="EmergingMarketsEquityMember"/>
					<link:label xlink:type="resource" xlink:label="label_EmergingMarketsEquityMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Emerging Markets Equity [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="EmergingMarketsEquityMember" xlink:to="label_EmergingMarketsEquityMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_UnitedKingdomEquityMember" xlink:label="UnitedKingdomEquityMember"/>
					<link:label xlink:type="resource" xlink:label="label_UnitedKingdomEquityMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">United Kingdom Equity [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="UnitedKingdomEquityMember" xlink:to="label_UnitedKingdomEquityMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_JapanEquityMember" xlink:label="JapanEquityMember"/>
					<link:label xlink:type="resource" xlink:label="label_JapanEquityMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Japan Equity [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="JapanEquityMember" xlink:to="label_JapanEquityMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NorthAmericaExUSEquityMember" xlink:label="NorthAmericaExUSEquityMember"/>
					<link:label xlink:type="resource" xlink:label="label_NorthAmericaExUSEquityMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">North America ex U S Equity [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="NorthAmericaExUSEquityMember" xlink:to="label_NorthAmericaExUSEquityMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_EuropeExUKEquityMember" xlink:label="EuropeExUKEquityMember"/>
					<link:label xlink:type="resource" xlink:label="label_EuropeExUKEquityMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Europe ex U K Equity [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="EuropeExUKEquityMember" xlink:to="label_EuropeExUKEquityMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_DevelopedMiddleEastAfricaMember" xlink:label="DevelopedMiddleEastAfricaMember"/>
					<link:label xlink:type="resource" xlink:label="label_DevelopedMiddleEastAfricaMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Developed Middle East Africa [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="DevelopedMiddleEastAfricaMember" xlink:to="label_DevelopedMiddleEastAfricaMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_USSmallMidCapMember" xlink:label="USSmallMidCapMember"/>
					<link:label xlink:type="resource" xlink:label="label_USSmallMidCapMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">U S Small Mid Cap [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="USSmallMidCapMember" xlink:to="label_USSmallMidCapMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_AsiaPacificExJapanMember" xlink:label="AsiaPacificExJapanMember"/>
					<link:label xlink:type="resource" xlink:label="label_AsiaPacificExJapanMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Asia Pacific ex Japan [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AsiaPacificExJapanMember" xlink:to="label_AsiaPacificExJapanMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_EuropeExUKMember" xlink:label="EuropeExUKMember"/>
					<link:label xlink:type="resource" xlink:label="label_EuropeExUKMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Europe ex U K [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="EuropeExUKMember" xlink:to="label_EuropeExUKMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NorthAmericaExUSMember" xlink:label="NorthAmericaExUSMember"/>
					<link:label xlink:type="resource" xlink:label="label_NorthAmericaExUSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">North America ex U S [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="NorthAmericaExUSMember" xlink:to="label_NorthAmericaExUSMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_EmergingMarketsMember" xlink:label="EmergingMarketsMember"/>
					<link:label xlink:type="resource" xlink:label="label_EmergingMarketsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Emerging Markets [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="EmergingMarketsMember" xlink:to="label_EmergingMarketsMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054209Member" xlink:label="C000054209Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054209Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054209 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054209Member" xlink:to="label_C000054209Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054209Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class R6</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054209Member" xlink:to="label_C000054209Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054208Member" xlink:label="C000054208Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054208Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054208 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054208Member" xlink:to="label_C000054208Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054208Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class R4</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054208Member" xlink:to="label_C000054208Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054217Member" xlink:label="C000054217Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054217Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054217 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054217Member" xlink:to="label_C000054217Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054217Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class R3</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054217Member" xlink:to="label_C000054217Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054216Member" xlink:label="C000054216Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054216Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054216 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054216Member" xlink:to="label_C000054216Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054216Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class R2</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054216Member" xlink:to="label_C000054216Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054214Member" xlink:label="C000054214Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054214Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054214 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054214Member" xlink:to="label_C000054214Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054214Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class R1</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054214Member" xlink:to="label_C000054214Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054212Member" xlink:label="C000054212Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054212Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054212 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054212Member" xlink:to="label_C000054212Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054212Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class I</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054212Member" xlink:to="label_C000054212Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054211Member" xlink:label="C000054211Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054211Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054211 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054211Member" xlink:to="label_C000054211Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054211Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class C</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054211Member" xlink:to="label_C000054211Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054210Member" xlink:label="C000054210Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054210Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054210 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054210Member" xlink:to="label_C000054210Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054210Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class B</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054210Member" xlink:to="label_C000054210Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000054207Member" xlink:label="C000054207Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000054207Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000054207 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054207Member" xlink:to="label_C000054207Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000054207Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class A</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000054207Member" xlink:to="label_C000054207Member_2"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherInvestmentsMember" xlink:label="OtherInvestmentsMember"/>
					<link:label xlink:type="resource" xlink:label="label_OtherInvestmentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Other Investments [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="OtherInvestmentsMember" xlink:to="label_OtherInvestmentsMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DefinedBenefitPlanEquitySecuritiesUsLargeCapMember" xlink:label="DefinedBenefitPlanEquitySecuritiesUsLargeCapMember"/>
					<link:label xlink:type="resource" xlink:label="label_DefinedBenefitPlanEquitySecuritiesUsLargeCapMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Defined Benefit Plan, Equity Securities, US, Large Cap [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="DefinedBenefitPlanEquitySecuritiesUsLargeCapMember" xlink:to="label_DefinedBenefitPlanEquitySecuritiesUsLargeCapMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsMember" xlink:label="CashAndCashEquivalentsMember"/>
					<link:label xlink:type="resource" xlink:label="label_CashAndCashEquivalentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Cash and Cash Equivalents [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CashAndCashEquivalentsMember" xlink:to="label_CashAndCashEquivalentsMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US" xlink:label="US"/>
					<link:label xlink:type="resource" xlink:label="label_US" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">UNITED STATES</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="US" xlink:to="label_US"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_GB" xlink:label="GB"/>
					<link:label xlink:type="resource" xlink:label="label_GB" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">UNITED KINGDOM</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="GB" xlink:to="label_GB"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_JP" xlink:label="JP"/>
					<link:label xlink:type="resource" xlink:label="label_JP" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">JAPAN</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="JP" xlink:to="label_JP"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_HeatingOilMember" xlink:label="HeatingOilMember"/>
					<link:label xlink:type="resource" xlink:label="label_HeatingOilMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Heating Oil [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="HeatingOilMember" xlink:to="label_HeatingOilMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NaturalGasReservesMember" xlink:label="NaturalGasReservesMember"/>
					<link:label xlink:type="resource" xlink:label="label_NaturalGasReservesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Natural Gas [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="NaturalGasReservesMember" xlink:to="label_NaturalGasReservesMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MoodysAaaRatingMember" xlink:label="MoodysAaaRatingMember"/>
					<link:label xlink:type="resource" xlink:label="label_MoodysAaaRatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Moody&apos;s, Aaa Rating [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="MoodysAaaRatingMember" xlink:to="label_MoodysAaaRatingMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_FitchAARatingMember" xlink:label="FitchAARatingMember"/>
					<link:label xlink:type="resource" xlink:label="label_FitchAARatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Fitch, AA Rating [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="FitchAARatingMember" xlink:to="label_FitchAARatingMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_FitchARatingMember" xlink:label="FitchARatingMember"/>
					<link:label xlink:type="resource" xlink:label="label_FitchARatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Fitch, A Rating [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="FitchARatingMember" xlink:to="label_FitchARatingMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_FitchBBBRatingMember" xlink:label="FitchBBBRatingMember"/>
					<link:label xlink:type="resource" xlink:label="label_FitchBBBRatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Fitch, BBB Rating [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="FitchBBBRatingMember" xlink:to="label_FitchBBBRatingMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USGovernmentDebtSecuritiesMember" xlink:label="USGovernmentDebtSecuritiesMember"/>
					<link:label xlink:type="resource" xlink:label="label_USGovernmentDebtSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">US Government Debt Securities [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="USGovernmentDebtSecuritiesMember" xlink:to="label_USGovernmentDebtSecuritiesMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FixedIncomeSecuritiesMember" xlink:label="FixedIncomeSecuritiesMember"/>
					<link:label xlink:type="resource" xlink:label="label_FixedIncomeSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Fixed Income Securities [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="FixedIncomeSecuritiesMember" xlink:to="label_FixedIncomeSecuritiesMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088951Member" xlink:label="C000088951Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088951Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088951 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088951Member" xlink:to="label_C000088951Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088952Member" xlink:label="C000088952Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088952Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088952 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088952Member" xlink:to="label_C000088952Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088953Member" xlink:label="C000088953Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088953Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088953 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088953Member" xlink:to="label_C000088953Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088954Member" xlink:label="C000088954Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088954Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088954 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088954Member" xlink:to="label_C000088954Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088955Member" xlink:label="C000088955Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088955Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088955 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088955Member" xlink:to="label_C000088955Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088956Member" xlink:label="C000088956Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088956Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088956 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088956Member" xlink:to="label_C000088956Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088957Member" xlink:label="C000088957Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088957Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088957 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088957Member" xlink:to="label_C000088957Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000088958Member" xlink:label="C000088958Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000088958Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000088958 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000088958Member" xlink:to="label_C000088958Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_C000119775Member" xlink:label="C000119775Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000119775Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000119775 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000119775Member" xlink:to="label_C000119775Member"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CommodityExposureMember" xlink:label="CommodityExposureMember"/>
					<link:label xlink:type="resource" xlink:label="label_CommodityExposureMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Commodity Exposure [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CommodityExposureMember" xlink:to="label_CommodityExposureMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_FederalAgenciesMember" xlink:label="FederalAgenciesMember"/>
					<link:label xlink:type="resource" xlink:label="label_FederalAgenciesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Federal Agencies [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="FederalAgenciesMember" xlink:to="label_FederalAgenciesMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NotRatedMember" xlink:label="NotRatedMember"/>
					<link:label xlink:type="resource" xlink:label="label_NotRatedMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Not Rated [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="NotRatedMember" xlink:to="label_NotRatedMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NonFixedIncomeMember" xlink:label="NonFixedIncomeMember"/>
					<link:label xlink:type="resource" xlink:label="label_NonFixedIncomeMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Non Fixed Income [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="NonFixedIncomeMember" xlink:to="label_NonFixedIncomeMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CashAndCashEquivalentsQualityMember" xlink:label="CashAndCashEquivalentsQualityMember"/>
					<link:label xlink:type="resource" xlink:label="label_CashAndCashEquivalentsQualityMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Cash And Cash Equivalents Quality [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CashAndCashEquivalentsQualityMember" xlink:to="label_CashAndCashEquivalentsQualityMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_OtherMember" xlink:label="OtherMember"/>
					<link:label xlink:type="resource" xlink:label="label_OtherMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Other [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="OtherMember" xlink:to="label_OtherMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_BrentCrudeMember" xlink:label="BrentCrudeMember"/>
					<link:label xlink:type="resource" xlink:label="label_BrentCrudeMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Brent Crude [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="BrentCrudeMember" xlink:to="label_BrentCrudeMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_GoldSectorMember" xlink:label="GoldSectorMember"/>
					<link:label xlink:type="resource" xlink:label="label_GoldSectorMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Gold Sector [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="GoldSectorMember" xlink:to="label_GoldSectorMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_WTICrudeOilMember" xlink:label="WTICrudeOilMember"/>
					<link:label xlink:type="resource" xlink:label="label_WTICrudeOilMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">WTI Crude Oil [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="WTICrudeOilMember" xlink:to="label_WTICrudeOilMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_UnleadedGasolineMember" xlink:label="UnleadedGasolineMember"/>
					<link:label xlink:type="resource" xlink:label="label_UnleadedGasolineMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Unleaded Gasoline [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="UnleadedGasolineMember" xlink:to="label_UnleadedGasolineMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SoybeansMember" xlink:label="SoybeansMember"/>
					<link:label xlink:type="resource" xlink:label="label_SoybeansMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Soybeans [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="SoybeansMember" xlink:to="label_SoybeansMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CornMember" xlink:label="CornMember"/>
					<link:label xlink:type="resource" xlink:label="label_CornMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Corn [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CornMember" xlink:to="label_CornMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_LiveCattleMember" xlink:label="LiveCattleMember"/>
					<link:label xlink:type="resource" xlink:label="label_LiveCattleMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Live Cattle [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="LiveCattleMember" xlink:to="label_LiveCattleMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CopperCOMEXMember" xlink:label="CopperCOMEXMember"/>
					<link:label xlink:type="resource" xlink:label="label_CopperCOMEXMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Copper COMEX [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CopperCOMEXMember" xlink:to="label_CopperCOMEXMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_GasOilMember" xlink:label="GasOilMember"/>
					<link:label xlink:type="resource" xlink:label="label_GasOilMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Gas Oil [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="GasOilMember" xlink:to="label_GasOilMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_AluminumMember" xlink:label="AluminumMember"/>
					<link:label xlink:type="resource" xlink:label="label_AluminumMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Aluminum [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AluminumMember" xlink:to="label_AluminumMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SoybeanOilMember" xlink:label="SoybeanOilMember"/>
					<link:label xlink:type="resource" xlink:label="label_SoybeanOilMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Soybean Oil [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="SoybeanOilMember" xlink:to="label_SoybeanOilMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SilverMember" xlink:label="SilverMember"/>
					<link:label xlink:type="resource" xlink:label="label_SilverMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Silver [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="SilverMember" xlink:to="label_SilverMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_NickelMember" xlink:label="NickelMember"/>
					<link:label xlink:type="resource" xlink:label="label_NickelMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Nickel [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="NickelMember" xlink:to="label_NickelMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SoybeanMealMember" xlink:label="SoybeanMealMember"/>
					<link:label xlink:type="resource" xlink:label="label_SoybeanMealMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Soybean Meal [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="SoybeanMealMember" xlink:to="label_SoybeanMealMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_ZincMember" xlink:label="ZincMember"/>
					<link:label xlink:type="resource" xlink:label="label_ZincMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Zinc [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="ZincMember" xlink:to="label_ZincMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CoffeeMember" xlink:label="CoffeeMember"/>
					<link:label xlink:type="resource" xlink:label="label_CoffeeMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Coffee [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CoffeeMember" xlink:to="label_CoffeeMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_LeanHogsMember" xlink:label="LeanHogsMember"/>
					<link:label xlink:type="resource" xlink:label="label_LeanHogsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Lean Hogs [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="LeanHogsMember" xlink:to="label_LeanHogsMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_FeederCattleMember" xlink:label="FeederCattleMember"/>
					<link:label xlink:type="resource" xlink:label="label_FeederCattleMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Feeder Cattle [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="FeederCattleMember" xlink:to="label_FeederCattleMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_WheatMember" xlink:label="WheatMember"/>
					<link:label xlink:type="resource" xlink:label="label_WheatMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Wheat [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="WheatMember" xlink:to="label_WheatMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_SugarMember" xlink:label="SugarMember"/>
					<link:label xlink:type="resource" xlink:label="label_SugarMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Sugar [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="SugarMember" xlink:to="label_SugarMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_PlatinumMember" xlink:label="PlatinumMember"/>
					<link:label xlink:type="resource" xlink:label="label_PlatinumMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Platinum [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="PlatinumMember" xlink:to="label_PlatinumMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CocoaMember" xlink:label="CocoaMember"/>
					<link:label xlink:type="resource" xlink:label="label_CocoaMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Cocoa [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CocoaMember" xlink:to="label_CocoaMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_KansasWheatMember" xlink:label="KansasWheatMember"/>
					<link:label xlink:type="resource" xlink:label="label_KansasWheatMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Kansas Wheat [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="KansasWheatMember" xlink:to="label_KansasWheatMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_CottonMember" xlink:label="CottonMember"/>
					<link:label xlink:type="resource" xlink:label="label_CottonMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Cotton [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CottonMember" xlink:to="label_CottonMember"/>
					<link:loc xlink:type="locator" xlink:href="#mstxv_LeadMember" xlink:label="LeadMember"/>
					<link:label xlink:type="resource" xlink:label="label_LeadMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Lead [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="LeadMember" xlink:to="label_LeadMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentTypeAxis" xlink:label="InvestmentTypeAxis"/>
					<link:label xlink:type="resource" xlink:label="label_InvestmentTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Investment Type [Axis]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="InvestmentTypeAxis" xlink:to="label_InvestmentTypeAxis" priority="1"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsNet" xlink:label="AssetsNet"/>
					<link:label xlink:type="resource" xlink:label="label_AssetsNet" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Net Assets</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AssetsNet" xlink:to="label_AssetsNet" priority="1"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyPortfolioTurnover" xlink:label="InvestmentCompanyPortfolioTurnover"/>
					<link:label xlink:type="resource" xlink:label="label_InvestmentCompanyPortfolioTurnover" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Investment Company Portfolio Turnover</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="InvestmentCompanyPortfolioTurnover" xlink:to="label_InvestmentCompanyPortfolioTurnover" priority="1"/>                
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_NoTradingSymbolFlag" xlink:label="dei_NoTradingSymbolFlag"/>
					<link:label xlink:type="resource" xlink:label="label_NoTradingSymbolFlag" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">No Trading Symbol Flag</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_NoTradingSymbolFlag" xlink:to="label_NoTradingSymbolFlag" priority="1"/>		
				</link:labelLink>
			</link:linkbase>
		</appinfo>
	</annotation>   
	<element name="AsiaPacificExJapanEquityMember" id="mstxv_AsiaPacificExJapanEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="EmergingMarketsEquityMember" id="mstxv_EmergingMarketsEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="UnitedKingdomEquityMember" id="mstxv_UnitedKingdomEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="JapanEquityMember" id="mstxv_JapanEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="NorthAmericaExUSEquityMember" id="mstxv_NorthAmericaExUSEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="EuropeExUKEquityMember" id="mstxv_EuropeExUKEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="DevelopedMiddleEastAfricaMember" id="mstxv_DevelopedMiddleEastAfricaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="USSmallMidCapMember" id="mstxv_USSmallMidCapMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="AsiaPacificExJapanMember" id="mstxv_AsiaPacificExJapanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="EuropeExUKMember" id="mstxv_EuropeExUKMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="NorthAmericaExUSMember" id="mstxv_NorthAmericaExUSMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="EmergingMarketsMember" id="mstxv_EmergingMarketsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054209Member" id="mstxv_C000054209Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054208Member" id="mstxv_C000054208Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054217Member" id="mstxv_C000054217Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054216Member" id="mstxv_C000054216Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054214Member" id="mstxv_C000054214Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054212Member" id="mstxv_C000054212Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054211Member" id="mstxv_C000054211Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054210Member" id="mstxv_C000054210Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000054207Member" id="mstxv_C000054207Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088951Member" id="mstxv_C000088951Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088952Member" id="mstxv_C000088952Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088953Member" id="mstxv_C000088953Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088954Member" id="mstxv_C000088954Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088955Member" id="mstxv_C000088955Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088956Member" id="mstxv_C000088956Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088957Member" id="mstxv_C000088957Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000088958Member" id="mstxv_C000088958Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="C000119775Member" id="mstxv_C000119775Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CommodityExposureMember" id="mstxv_CommodityExposureMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="FederalAgenciesMember" id="mstxv_FederalAgenciesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="NotRatedMember" id="mstxv_NotRatedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="NonFixedIncomeMember" id="mstxv_NonFixedIncomeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CashAndCashEquivalentsQualityMember" id="mstxv_CashAndCashEquivalentsQualityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="OtherMember" id="mstxv_OtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="BrentCrudeMember" id="mstxv_BrentCrudeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="GoldSectorMember" id="mstxv_GoldSectorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="WTICrudeOilMember" id="mstxv_WTICrudeOilMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="UnleadedGasolineMember" id="mstxv_UnleadedGasolineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="SoybeansMember" id="mstxv_SoybeansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CornMember" id="mstxv_CornMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="LiveCattleMember" id="mstxv_LiveCattleMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CopperCOMEXMember" id="mstxv_CopperCOMEXMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="GasOilMember" id="mstxv_GasOilMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="AluminumMember" id="mstxv_AluminumMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="SoybeanOilMember" id="mstxv_SoybeanOilMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="SilverMember" id="mstxv_SilverMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="NickelMember" id="mstxv_NickelMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="SoybeanMealMember" id="mstxv_SoybeanMealMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="ZincMember" id="mstxv_ZincMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CoffeeMember" id="mstxv_CoffeeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="LeanHogsMember" id="mstxv_LeanHogsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="FeederCattleMember" id="mstxv_FeederCattleMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="WheatMember" id="mstxv_WheatMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="SugarMember" id="mstxv_SugarMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="PlatinumMember" id="mstxv_PlatinumMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CocoaMember" id="mstxv_CocoaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="KansasWheatMember" id="mstxv_KansasWheatMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CottonMember" id="mstxv_CottonMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="LeadMember" id="mstxv_LeadMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
</schema>
