问题补充：
- Jack is in a bad mood because he failed in yesterday’s exam.
- ? As far as I know, he is doing fine work at school.
A. How come
B. So what
C. What’s it all about
D. Have you got that
答案：
(答案→)A. How come
B. So what
C. What’s it all about
D. Have you got that
解析：考查交际用语。A怎么会？B那又怎么样？C关于…? D 你怎么知道的？结合句意可知A正确。句意：—因为昨天考试不及格，杰克的情绪很不好。—怎么会？据我所知，他在学校表现很好。
