题目

Good afternoon! Welcome to England. We hope that your visit here will be a pleasant one. Now, I would like to tell you something about our laws.    The first one is about drinking. Now, you may not buy wine in this country, if you are under 18 years of age. Neither may your friends buy it for you.    The second one: noise. Enjoy yourselves by all means, but please don't make unnecessary noise, especially at night. We ask you to respect other people who may wish to be quiet.    The third one: crossing the road. Be careful. The traffic moves on the left side of the road in this country. UsA、B两种烃的混合物，当混合物的质量一定时，无论A、B以何种比例混合，完全燃烧产生的CO2的量均相等。在① 同分异构体，② 同系物，③ 具有相同的最简式，④ 含碳的质量分数相同中符合上述条件的组合是A.①②④B.①③④C.②③④D.①②③