第23题: [单项选择]Caffeine ______ if you want to have a good sleep. A. should be taken seven hours earlier B. should not be taken C. should be taken two or three hours earlier D. should be taken little 参考答案:D 答案解析:解析:由文章第九段第一行Avoid caffeine. Caffeine is a common disrupter of sleep可知,如果你想睡个好觉,不要摄人太多咖啡因。