下列哪种原因造成的贫血是小细胞性贫血（）。

A.叶酸缺乏

B.使用齐多夫定（AZT）

C.甲状腺机能减退

D.酗酒

E.海洋性贫血

9. _____frightened us ____the electricity was suddenly cut off, which threw all of us into the dark.

A． It was; that

B．What was; most was that

C． It ; most what

D． What; most was that