单选题Water,whichseemssosimpleandcommon,

单选题 Water, which seems so simple and common, is ______ makes life possible.A.whatB.thatC.whichD.how

A解析试题分析：考查表语从句：句意：看似简单普通的水，是使得生命可能的东西。Is后面是表语从句，表语从句缺少主语，用what。选A。考点：考查表语从句点评：连接表语从句的连接词有：that, what, who, when, where, which, why, whether, how, whoever，whomever，whichever ，whatever等。还有如because, as if, as though等。解答这类题目，关键在于分析清楚句子结构。通过判断引导词在从句中所作的成分及意义，来选择正确的引导词。

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