–What is the theme about for the meeting this evening?.No idea. Perhaps we will have to

问题补充：

–What is the theme about for the meeting this evening?.

--No idea. Perhaps we will have to discuss the plan a few days later.

A. carried out

B. being carried out

C. to be carried out

D. carrying out

答案：

A. carried out

B. being carried out

(答案→)C. to be carried out

D. carrying out

解析：本题考查非谓语动词。根据语境计划还未执行，故用不定式作宾语补足语，选C。