2) —I’m sorry to have kept you waiting.
   —______, Bill.   
   A. You’re welcome   B. Go ahead    C. Don’t mention it     D. No problem
点拨:选D。对道歉的应答常见的有:That’s all right /That’s OK / That’s nothing / Never mind / It doesn’t matter / No problem等,意为“没关系”。而Don’t mention it是用来回答对方表示感谢时的用语。