—— May I see you at 4 o’clock this afternoon?—— I’m afraid not I a charity meeting then.A

问题补充：

—— May I see you at 4 o’clock this afternoon?

—— I’m afraid not, I a charity meeting then.

A. will attend

B. have attended

C. will be attending

D. was attending

答案：

A. will attend

B. have attended

(答案→)C. will be attending

D. was attending

解析： 考查时态，句意：我可以在今天下午四点见你好吗？恐怕不行，那个时候我将正在参加一个慈善会议。根据语境指的是将来某一时刻正在进行的动作，所以应用将来进行时态。选C。