—The police have caught the murderer.　　 —Yes and he admitted his boss on a rainy night s

问题补充：

—The police have caught the murderer.

—Yes, and he admitted his boss on a rainy night seven years ago.

A. to kill

B. to have killed

C. having killed

D. have been killing

答案：

A. to kill

B. to have killed

(答案→)C. having killed

D. have been killing

解析：在delay, admit, avoid, suggest, advise, practise, finish, mind, enjoy等动词后,只跟动名词而不跟动词不定式作宾语。错答B者只考虑到kill动作发生在admit之前,但不知admit doing这一用法。