单选题
1分
President Xi Jinping highlighted the importance of improvement of ecology and environmental protecti...
President Xi Jinping highlighted the importance of improvement of ecology and environmental protection as he __________ greater awareness of their benefits.
参考答案: D
参考解析: 考查动词短语辨析。call on“请求,要求(某人做某事)”;call in“打电话来,叫来”;call up“给……打电话”:call for后面接表示事物的名词时,表示“需要,要求”。句意为“当习近平主席要求提高对改善生态及环境保护的益处的意识时,强调了它们的重要性”。故选D。