is surprising to us is that Tom can speak English fluently as though he were a native spea

问题补充：

is surprising to us is that Tom can speak English fluently as though he were a native speakdr.

A. What

B. That

C. Which

D. As

答案：

(答案→)A. What

B. That

C. Which

D. As

解析：考查主语从句：句意：使我们惊讶的是汤姆能自由的说英语好像是当地人。What引导的是主语从句，在主语从句中what做主语，选A。