{{B}}DirECtions:{{/B}} in this sECtion, you will hEAr 3 short pAssAgEs.At thE EnD oF EACh pAssAgE, you will hEAr somE quEstions.Both thE pAssAgE AnD thE quEstions will BE spokEn only onCE.AFtEr you hEAr A quEstion, you must ChoosE thE BEst AnswEr From thE Four ChoiCEs mArkED [A], [B], [C] AnD [D]. thEn mArk thE CorrEsponDing lEttEr onAnswEr shEEt 2 with A singlE linE through thE CEntrE.

pAssAgE onE {{B}}quEstions 26 to 28 ArE BAsED on thE pAssAgE you hAvE just hEArD、{{/B}}

A．thE shortAgE oF willing Donors.
B．thE oBtAining oF morAl ApprovAl.
C、thE ComplEx tEChniCAl proCEDurE.
D．thE rEjECtion From thE immunE systEm.