— I need to advertise for a second-hand mountain bike.
— ？David just plans to sell his present one.
A. Why bother
B. Why not
C. So what
D. What for
网友回答
(答案→)A. Why bother
B. Why not
C. So what
D. What for
解析：考查交际用语Why bother没有必要；Why not为什么不；So what那又怎样；What for为何。句意：我需要登广告买一辆二手的山地车。没必要，戴维正要把他那辆卖掉呢。选A。