题干

苯环结构中不存在C﹣C单键与C=C双键的交替结构,可以作为证据的是(   )

①苯能使溴水萃取分层

②苯不能使酸性高锰酸钾溶液褪色

③苯在一定条件下既能发生取代反应,又能发生加成反应

④经测定,邻二甲苯只有一种结构

⑤经测定,苯环上碳碳键的键长相等.

A:④⑤

B:①②③⑤

C:①②③

D:②④⑤

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答案(点此获取答案解析)

D

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阅读下面短文,从短文后各题所给的四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项。

    For fans of Emma Watson, it's quite exciting that she perfectly plays the role of Belle in Disney's fantasy film Beauty and the Beast. In most fairy tales, it's the woman who 1her prince to rescue her from danger, but in this movie, Belle, independent and active, with 2and kindness, saves her love and 3him from a fearsome beast back into a charming prince.

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    On March 8, Watson 11 a live Question and Answer about gender equality for the UN's HeForShe campaign. During the12, Watson emphasized that gender equality doesn't just 13 women. “I've got four brothers. Gender equality is having an effect on them just as 14 as me. My brother once said he just couldn't 15 some of his male friends, 16the rude way they talk about girls.”

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