It is recognized that the part the UN plays in international relations is important.A. i

It is recognized that the part the UN plays in international relations is important.
A. in which
B. where
C. that
D. of which

A. in whichB. where(答案→)C. thatD. of which解析：考查定语从句。the part是先行词，play a part in在......中扮演角色，定语从句缺少宾语，用that/which引导定语从句；A、B作状语，D作定语，相当于whose，排除A、B、D。故选C。

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