问题补充：
surprised me most was that she had become a famous singer.
A. That
B. It
C. What
D. This
答案：
A. That
B. It
(答案→)C. What
D. This
解析：what surprised me most 在本题中是主语从句。如果选B, 则应把原题中的was去掉，变为：It surprised me most that she had become a famous singer. (it做形式主语)
