The next king of Prussia, Fretrick WilliamⅠ, the Amber Room belonged, decided not to keep

The next king of Prussia, Fretrick WilliamⅠ, the Amber Room belonged, decided not to keep it.
A. to which
B. to whom
C. in which
D. in whom

A. to which(答案→)B. to whomC. in whichD. in whom解析：考查定语从句。先行词为Fretrick WilliamⅠ，短语：belong to 属于，所以此空应填to whom，选B。

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