The doctor told him that he should take a holiday to relax himself but didn’t help.A. wh

问题补充：

The doctor told him that he should take a holiday to relax himself, but didn’t help.

A. which

B. that

C. it

D. he

答案：

A. which

B. that

(答案→)C. it

D. he

解析：句意：医生告诉他，他应该休假来放松自己，但是没有用。根据句意可知下文代词指代的是前文提到的休假一事，做下文逻辑主语。选项ABD没有这个用法。故选C。