选哪个,请给出原因.A.make it clear B.make that clear C.make this clear D.make clear

题目

选哪个,请给出原因.A.make it clear B.make that clear C.make this clear D.make clear
This is the most important assignment facing American journalism-to
____________to the readers the problems of the day,and make international news as undersatandable as community news.
不选A

答案

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应该选D.