Question

--- What on earth are the police busy with?
--- They have been investigating how the train crash __________.

A．came out

B．came across

C．came about

D．came up

Answer 1

C

解析试题分析：句意为：----警察们究竟在忙什么呢？ ---他们正在调查这次火车相撞的原因（是怎么发生的）. come out 出版，发行，发现； come across偶然遇到，碰到；come about 发生，产生；come up 想出，提出。故答案应为C。
考点：考查动词短语的含义。