It is not rare in_____ that people in ______ fifties are going to university for further education．

A．90s ; the

B．the 90s; /

C．90s; their

D．the 90s ; their

血小板第3因子有效性测定结果为活性减低时，符合下列哪项疾病（）

A.血小板增多症

B.原发性血小板减少性紫癜

C.继发性血小板减少性紫癜

D.血小板无力症

E.以上都对