When asked about this major traffic accident the policeman said it should not have if th

问题补充：

When asked about this major traffic accident, the policeman said it should not have if the driver hadn’t been speeding.

A. come out

B. come about

C. come across

D. happen

答案：

A. come out

(答案→)B. come about

C. come across

D. happen

解析：考查动词短语辨析。should have后接过去分词，排除D；come out“出来，出版”；come across“偶遇”；come about“发生”。句意“如果司机不加速的话就不会发生了”。故选B。