— Are you getting a new apartment this year?— I can’t afford to pay my bills. How can I bu

问题补充：

— Are you getting a new apartment this year?

— I can’t afford to pay my bills. How can I buy a new apartment?

A. Don’t mention it.

B. You must be joking.

C. Are you sure?

D. Good idea!

答案：

A. Don’t mention it.

(答案→)B. You must be joking.

C. Are you sure?

D. Good idea!

解析：本句回答语的含义是我卖不起新的公寓，你一定在开玩笑意思才符合句意，You must be joking表示此意，故本题选B。