—What about your TEFL test?

—I have answered all the questions, but I’m not sure _____ I could get a high enough score. 

A．what

B．if

C．when

D．why

输血需加温的是（）。

A.输血3U

B.输血速度30ml／分

C.换血疗法或输血时患者静脉痉挛

D.受血者有温抗体

E.输机采血小板