题干

北京时闻2018年2月22日,在平昌冬奥会短道速滑男子500米决赛中。武大靖勇夺中国体育代表团在本届奥运会上的首金。在剧烈的高强度运动中,人体有些部位会感到酸痛,这是因为体内产生了乳酸(化学式为C3H6O3),下列叙述错误的是(   )

A:乳酸是由三种元素组成的有机物

B:乳酸是由乳酸分子构成的

C:乳酸中质子数等于中子数

D:乳酸中三种元素的质量比和葡萄糖相同

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答案(点此获取答案解析)

C

同类题2

阅读下列短文,从每题所给的四个选项(A、B、C和D)中选出最佳选项。

    "Good evening, everyone. As we celebrate International Dog Day, I wanted to focus on a specific type of dog that is perhaps the most misunderstood breed in the world—the pit bull. It makes me unhappy that public opinion about pit bulls is that they are extremely dangerous. If a pit bull is that meaning, that's only as a result of being taught to fight other dogs to the death in dogfights. The truth is that a pit bull is very faithful and loving.

    "A pit bull is a cross between a terrier and a bulldog. That's why their coloring can be different from one dog to the next. Pit bulls all have short fur. They came over to the U.S. from Britain with their immigrant farming families. Pit bulls guarded the cows, sheep and family from thieves. They were beloved members of the family because they were so faithful and loving. They were also very strong, especially their jaws.

    "Unfortunately, bad men turned a good thing into a bad thing. Since these dogs will do anything to please their masters, it was easy for these men to teach the dogs to be killers. Dogs fought other dogs in fenced "pits". Dog fighting became illegal(非法的) in the U.S. in 1875, but it still goes on. Today, pit bulls continue to be farm dogs, but they are also trained as police dogs, search dogs and of course they make great pets!

    "I have a pit bull myself. Piper is the friendliest dog you'll ever meet. He sleeps next to me at night. Even though he is an adult dog now, he still acts like a puppy sometimes. He would never bite me or anyone else! With proper and loving training, pit bulls are the best pets ever!"