----I’m sorry to have kept you waiting.--A. You are welcomeB. Go aheadC. Don’t mention

问题补充：

----I’m sorry to have kept you waiting.

----

A. You are welcome

B. Go ahead

C. Don’t mention it

D. No problem

答案：

A. You are welcome

B. Go ahead

C. Don’t mention it

(答案→)D. No problem

解析：-I’m sorry的回答有No problem，it doesn’t matter，it’s ok，it’s all right，never mind