Nuclear power's danger to health, safety, and even life itself can be summed up in one word: radiation. Nuclear radiation has a certain mystery about it, partly because it cannot be detected by human senses. It can't be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around us but we can't detect them, sense them, without a radio receiver. Similarly, we can't sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things. At very high levels, radiation can kill an animal or human being outright by killing masses of cells in vital organs. But even the lowest levels can do serious damage. There is no level of radiation that is completely safe. If the radiation does not hit anything important, the damage may not be significant. This is the case when only a few cells are hit, and if they are killed outright, your body will replace the dead cells with healthy ones. But if the few cells are only damaged, and if they reproduce themselves, you may be in trouble. They reproduce themselves in a deformed way. They can grow into cancer. Sometimes this does not show up for many years. This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the victim being aware at the time that damage has occurred. A person can be irradiated and feel fine, then die of cancer five, ten, or twenty years later as a result. Or a child can be born weak or liable to serious illness as a result of radiation absorbed by its grandparents. Radiation can hurt us. We must know the truth.

单选题 According to the passage, the danger of nuclear power lies in______.

【正确答案】 D

【答案解析】解析：文章第一段“Nuclear power’s danger to health，safety，and even life itself can be summed up in one word：radiation．”这句话对可能的危险做了一个整体的概括，指出了核能的危险在于“核辐射”，也即为D项的内容。A、B、C项的内容在文中都有提及，但都没有说它们对人体有危险。所以本题的正确答案应为D。

单选题 Radiation can cause serious consequences even at the lowest level______.

【正确答案】 B

【答案解析】解析：通过阅读第三段，我们可知在本段中作者讲到，高强度的核辐射能够立即杀死人或动物，最低强度的辐射也能造成严重的后果。任何强度的辐射都不可能绝对安全。如果立即杀死少量的细胞时，身体会有健康的细胞去代替，而损害的细胞有可能会畸形再生演变成癌。可见，A项不对，杀死的细胞会有健康的新细胞去代替，不会造成严重后果。文章并没有说受伤的细胞会自我修复，只是假设它能自我恢复。所以C项不对。根据第三段的内容我们也可以推知：只要受损害的细胞不再生是不会有任何严重后果的。所以D项不对。因此本题的正确答案应为B，它伤害很少的细胞有可能会引发癌症。

单选题 The word "significant" in Paragraph 3 most probably means______.

【正确答案】 C

【答案解析】解析：文章第三段“If the radiation does not hit anything important，the damage may not be significant．”如果辐射没有伤害到任何重要的器官，那么所造成的损害可能就不严重。接下来论述了高强度辐射的严重危害：“At very high levels，radiation can kill an animal or human being outright by killing masses of cells in vital organs．”所以该单词的意思应该是“致命的”，因为它可以导致人死亡的严重后果。C项与文章的意思相符。所以应该选C。

单选题 Radiation can hurt us in the way that it can______.

【正确答案】 D

【答案解析】解析：文章第三段第一句话，“当核辐射处于高强度时，它通过杀死重要器官内的大量细胞，使动物和人立刻死亡”。所以A项正确。第四段提到“一个人被辐射后可能感觉正常，结果在5年、10年或20年后死于癌症”。可见，核辐射可能伤害人体的一些细胞，多年以后引发癌症。所以B正确。第四段中同样提到了核辐射对后代的影响：一个小孩可能生来就身体弱或是容易患重病，是因为他们的祖父母吸收了辐射。所以C项也正确。因此本题的正确答案应该是D。

单选题 Which of the following can be best inferred from the passage?

【正确答案】 A

【答案解析】解析：根据文章内容可知：作者首先讲了核辐射的神秘性，即甚至它可能就在我们周围也不能被看到、听到、触摸到、闻到，紧接着作者讲到了它的危害性。可见，不能因为我们感觉不到核辐射，就认为强调人们要免受核辐射是不现实的。所以A项所说的“保护人们免受核辐射的重要性怎么强调都不过分”与文章的意思相符。在文中作者提到了人们之所以认为核辐射神秘的两个原因，可见人们对核辐射的神秘已经有所了解了，所以B项不对。文章讲到了辐射会造成癌症，但引起癌症的原因是多方面的，文中并没有说癌症主要是因辐射引起的，所以C项也不对。文中讲到“在辐射发生损害时，受害者不能意识到自己遭受到严重伤害”，所以无论有没有意识到辐射危险性的人都可能受到了辐射的伤害，所以D项也不对。因此本题的正确答案为A。