Li Gang was required to apologize the people present at the meeting what he had done .A.

问题补充：

Li Gang was required to apologize the people present at the meeting what he had done .

A. for ; by

B. with ; about

C. to ;for

D. at ; with

答案：

A. for ; by

B. with ; about

(答案→)C. to ;for

D. at ; with

解析：考查介词：句意：李刚被要求因为他做的事情，向到会的人道歉。Apologize to sb. for sth因为某事向某人道歉，选C。