What‘s the main idea of this passage? 查看材料 A.Experts are'concerned about excessive drinking in teenagers． B.The harm of e-cigarettes is greater than that of alcohol． C.Teenagers are in danger of risking their health on e-cigarettes． D.Researchers are aware of smoke-related health hazards．
A.Experts B. B.The C. C.Teenagers D. D.Researchers E.
【参考答案】
C 定位：由题干中的themainideaofthispassage可知，需结合全文进行分析。详解;主旨大意题。......