It was a time_______ the killer whales helped the whalers catch the baleen whales.

A．when

B．that

C．then

D．which

治疗凝血因子缺乏所致渗血应用（）。

A.红细胞混悬液

B.少浆全血

C.新鲜冷冻血浆

D.血小板

E.新鲜全血