NBME 25 QUESTIONS WITH CORRECT ANSWERS 2026
1
ExamBSectionB1:BItemB1BofB50
NationalBBoardBofBMedicalBExaminers
ComprehensiveBBasicBScienceBSelf-Assessment
1.BA75-year-
oldBmanBhasBdecreasedBexerciseBtoleranceBandBoccasionalBsyncopalBepisodesBrelatedBtoBexertion.B
Left-heartBcatheterizationBdisclosesBthisBpressureBtracingB(AoB-aorta;BLVB-leftBventricle;BLAB-
leftBatrium).BTheBmostBfrequentlyBencounteredBmechanismBunderlyingBthisBdisorderBisBwhichBofBt
heBfollowing?
ЕCG
A)BAmyloidBdeposition
150-
B)BCalcification
C)BCysticBmedialBnecrosis
D)BPericardialBeffusion
100-
OBE)BSeptalBhypertrophy
Ao
50-
LV
LA
Time
Time-
CorrectBAnswer:BB.
,TheBpressureBtracingBdemonstratesBaBlargeBpressureBgradientBbetweenBtheBleftBventricleBandBaort
aBduringBsystole,BwhichBisBconsistentBwithBtheBdiagnosisBofBaorticBstenosis.BInBtheBsettingBofBaorticB
stenosis,BtheBleftBventricleBmustBgenerateBhigherBpressuresBinBorderBto
overcomeBtheBopeningBresistanceBofBtheBstenoticBvalve.BThisBincreasedB-BCORRECTBANSWERSB-
2
ExamBSectionB1:BItemB2BofB50
NationalBBoardBofBMedicalBExaminers
ComprehensiveBBasicBScienceBSelf-Assessment
2.BNewBreagentsBareBbeingBdesignedBtoBtreatBgraft-versus-hostBdiseaseBinBHLA-
unrelatedBboneBmarrowBtransplantBrecipients.BReagentsBshouldBbeBdesignedBthatBselectivelyBdepl
eteBwhichBofBtheBfollowingBdonorBcells?
A)BBBlymphocytes
OBB)BDendriticBcells
C)BMacrophages
D)BNeutrophils
E)BTBlymphocytes
CorrectBAnswer:BE.
TBlymphocytes,BwhichBareBresponsibleBforBtheBimmuneBattackBagainstBtheBrecipient,BshouldBbeBth
eBtargetBofBagentsBusedBtoBtreatBgraft-versus-hostBdiseaseB(GVHD)BinBHLA-
unrelatedBboneBmarrowBtransplantBrecipients.BPriorBtoBgraftingBofBallogeneicBstemBcellsBinBaBbone
marrowBtransplant,BrecipientBnativeBmarrowBmustBbeBcompletelyBablated.BItBisBthenBreplacedBwit
hBdonorBmarrow,BwhichBrecolonizesBtheBmarrowBcavity.BSuccessfulBtransplantationBresultsBinBreco
nstitutionBofBtheBimmuneBsystemBwithBtheBdonor'sBiB-BCORRECTBANSWERSB-
3
ExamBSectionB1:BItemB3BofB50
NationalBBoardBofBMedicalBExaminers
,ComprehensiveBBasicBScienceBSelf-Assessment
3.BA9-year-oldBboyBhasBhadBalopeciaBandBhypocalcemiaBsinceBbirth.BHisBserumB1,25-
dihydroxycholecalciferolBconcentrationBisBwithinBtheBreferenceBrange,BserumB24,25-
dihydroxycholecalciferolBisBundetectable.BSerumBparathyroidBhormoneBconcentrationBisBabove
theBupperBlimitBofBtheBlaboratoryBassayBandBneedsBtoBbeBreassayedBatBaBdilution.BTheBresultsBareBp
ending.BWhichBofBtheBfollowingBisBtheBmostBlikelyBcauseBofBhisBcondition?
OBA)BLoss-of-functionBmutationBinBtheBcalcium-sensingBreceptor
B)BMultipleBendocrineBneoplasiaBtypeBI
C)BMutationsBinactivatingBtheBvitaminBDB24-hydroxylaseBgene
D)BMutationsBinactivatingBtheBvitaminBDBreceptor
CorrectBAnswer:BD.
VitaminBDBplaysBaBroleBinBserumBcalciumBandBphosphateBhomeostasisBbyBpromotingBtheBintestinalB
absorptionBofBcalciumBandBphosphate.BParathyroidBhormoneB(PTH)BalsoBhB-BCORRECTBANSWERSB-
4
ExamBSectionB1:BItemB4BofB50
NationalBBoardBofBMedicalBExaminers®
ComprehensiveBBasicBScienceBSelf-Assessment
4.BAssumingBtheBpositiveBpredictiveBvalueBofBaBtestBisB50%BandBtheBnegativeBpredictiveBvalueBisB75
%,BwhichBofBtheBfollowingBtablesBareBconsistentBwithBtheseBvalues?
Disease
Disease
Present
Absent
Present
Absent
A
, B
Positive
50
50
750
250
Test
Negative
250
750
50
50
Positive
250
750
50
50
Test
Negative
50
50
750
250
EBCannotBbeBdeterminedBfromBdataBgiven
A)
B)
1
ExamBSectionB1:BItemB1BofB50
NationalBBoardBofBMedicalBExaminers
ComprehensiveBBasicBScienceBSelf-Assessment
1.BA75-year-
oldBmanBhasBdecreasedBexerciseBtoleranceBandBoccasionalBsyncopalBepisodesBrelatedBtoBexertion.B
Left-heartBcatheterizationBdisclosesBthisBpressureBtracingB(AoB-aorta;BLVB-leftBventricle;BLAB-
leftBatrium).BTheBmostBfrequentlyBencounteredBmechanismBunderlyingBthisBdisorderBisBwhichBofBt
heBfollowing?
ЕCG
A)BAmyloidBdeposition
150-
B)BCalcification
C)BCysticBmedialBnecrosis
D)BPericardialBeffusion
100-
OBE)BSeptalBhypertrophy
Ao
50-
LV
LA
Time
Time-
CorrectBAnswer:BB.
,TheBpressureBtracingBdemonstratesBaBlargeBpressureBgradientBbetweenBtheBleftBventricleBandBaort
aBduringBsystole,BwhichBisBconsistentBwithBtheBdiagnosisBofBaorticBstenosis.BInBtheBsettingBofBaorticB
stenosis,BtheBleftBventricleBmustBgenerateBhigherBpressuresBinBorderBto
overcomeBtheBopeningBresistanceBofBtheBstenoticBvalve.BThisBincreasedB-BCORRECTBANSWERSB-
2
ExamBSectionB1:BItemB2BofB50
NationalBBoardBofBMedicalBExaminers
ComprehensiveBBasicBScienceBSelf-Assessment
2.BNewBreagentsBareBbeingBdesignedBtoBtreatBgraft-versus-hostBdiseaseBinBHLA-
unrelatedBboneBmarrowBtransplantBrecipients.BReagentsBshouldBbeBdesignedBthatBselectivelyBdepl
eteBwhichBofBtheBfollowingBdonorBcells?
A)BBBlymphocytes
OBB)BDendriticBcells
C)BMacrophages
D)BNeutrophils
E)BTBlymphocytes
CorrectBAnswer:BE.
TBlymphocytes,BwhichBareBresponsibleBforBtheBimmuneBattackBagainstBtheBrecipient,BshouldBbeBth
eBtargetBofBagentsBusedBtoBtreatBgraft-versus-hostBdiseaseB(GVHD)BinBHLA-
unrelatedBboneBmarrowBtransplantBrecipients.BPriorBtoBgraftingBofBallogeneicBstemBcellsBinBaBbone
marrowBtransplant,BrecipientBnativeBmarrowBmustBbeBcompletelyBablated.BItBisBthenBreplacedBwit
hBdonorBmarrow,BwhichBrecolonizesBtheBmarrowBcavity.BSuccessfulBtransplantationBresultsBinBreco
nstitutionBofBtheBimmuneBsystemBwithBtheBdonor'sBiB-BCORRECTBANSWERSB-
3
ExamBSectionB1:BItemB3BofB50
NationalBBoardBofBMedicalBExaminers
,ComprehensiveBBasicBScienceBSelf-Assessment
3.BA9-year-oldBboyBhasBhadBalopeciaBandBhypocalcemiaBsinceBbirth.BHisBserumB1,25-
dihydroxycholecalciferolBconcentrationBisBwithinBtheBreferenceBrange,BserumB24,25-
dihydroxycholecalciferolBisBundetectable.BSerumBparathyroidBhormoneBconcentrationBisBabove
theBupperBlimitBofBtheBlaboratoryBassayBandBneedsBtoBbeBreassayedBatBaBdilution.BTheBresultsBareBp
ending.BWhichBofBtheBfollowingBisBtheBmostBlikelyBcauseBofBhisBcondition?
OBA)BLoss-of-functionBmutationBinBtheBcalcium-sensingBreceptor
B)BMultipleBendocrineBneoplasiaBtypeBI
C)BMutationsBinactivatingBtheBvitaminBDB24-hydroxylaseBgene
D)BMutationsBinactivatingBtheBvitaminBDBreceptor
CorrectBAnswer:BD.
VitaminBDBplaysBaBroleBinBserumBcalciumBandBphosphateBhomeostasisBbyBpromotingBtheBintestinalB
absorptionBofBcalciumBandBphosphate.BParathyroidBhormoneB(PTH)BalsoBhB-BCORRECTBANSWERSB-
4
ExamBSectionB1:BItemB4BofB50
NationalBBoardBofBMedicalBExaminers®
ComprehensiveBBasicBScienceBSelf-Assessment
4.BAssumingBtheBpositiveBpredictiveBvalueBofBaBtestBisB50%BandBtheBnegativeBpredictiveBvalueBisB75
%,BwhichBofBtheBfollowingBtablesBareBconsistentBwithBtheseBvalues?
Disease
Disease
Present
Absent
Present
Absent
A
, B
Positive
50
50
750
250
Test
Negative
250
750
50
50
Positive
250
750
50
50
Test
Negative
50
50
750
250
EBCannotBbeBdeterminedBfromBdataBgiven
A)
B)
