单选题Those were the graduate&n

单选题 Those were the graduate assistants ______ to do the research work in the lab.A.to whom it was their responsibilityB.whose responsibility there wasC.whose responsibility wasD.of whom with the responsibility

C解析此题考查属格关系代词引导的定语从句，[A]、D.项应先排除；B.项从句的谓语为there be结构，讲不通；因此只有[C]项为正确

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