The Education Department says that school safety has set off alarm bells with frequent rep

The Education Department says that school safety has set off alarm bells with frequent reports of serious accidents students got injured or killed.
A. after which
B. in which
C. by which
D. for which

A. after which(答案→)B. in whichC. by whichD. for which解析：考查定语从句。代替指物的先行词accidents，在从句中作地点状语，所以用in which。后半部分意为“学生在事故中受伤或死亡”。

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