What’s really needed, according to most researchers in this field, ________ a“killer”application(应用)particularly suited for the way DNA puting solves problems．A.beingB.areC.isD.was
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C解析从句子结构看，What’s really needed为主语从句，所选的应是句子的谓语，并且应为单数，可排除A、B两项；What’s是What is的缩写，为现在时态，所以谓语也用一般现在时。