---I have cleaned the room three times a day. Look It is a mess again.-! Wait until th

问题补充：

---I have cleaned the room three times a day. Look, It is a mess again.

---! Wait until the children go to bed.

A. How come

B. Why bother

C. So what

D. What for

答案：

A. How come

(答案→)B. Why bother

C. So what

D. What for

解析：考查交际用语：A. How come怎么回事？ B. Why bother为什么费事？C.So what 那又怎样？ D. What for为什么？句意：--我一天打扫三次房间，看，又脏了？--别费事了！等孩子睡觉吧。选B。