Not until Mr. Smith came to China ______what kind of a country she is from.

A．Didn’t he know

B．Had he known

C．Hadn’t he known

D．Did he know

与If、Hf缺陷相关的疾病（）

A.肾小球肾炎

B.遗传性血管神经性水肿

C.严重感染

D.CIC清除障碍

E.阵发性夜间血红蛋白尿