You’d better make a mark you have any questions.A. at which 　B. at where 　C. the place 　D

You’d better make a mark you have any questions.
A. at which 　
B. at where 　
C. the place 　
D. where

A. at which 　B. at where 　C. the place 　(答案→)D. where解析：句意：你最好在有疑问的地方做个标记。考查地点状语从句。所以用where引导。如果加上at可以改成 at a/the place where ，where 在这儿引导的定语从句。place 做了at的宾语。

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