It never occurred to me you could succeed in persuading him to change his mindA. whichB.

问题补充：

It never occurred to me you could succeed in persuading him to change his mind．

A. which

B. what

C. that

D. if

答案：

A. which

B. what

(答案→)C. that

D. if

解析：考查主语从句。It是形式主语，真正的主语是 you could succeed in persuading him to change his mind这一主语从句，且从句不缺成分，句意完整，所以用that引导。选C。