单选题 A: I'm sorry that I can't go to your party tonight.
B: ______? Haven't we agreed on it?

【正确答案】 D
【答案解析】[注释] 口语中常用“How is it(that)…?”询问“什么原因使得”……?”。此句还可用“Why not?”回答,但不用“Why don't you…?”