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help see see, one question in feifeicr90, thanks!

38. Amphibian populations are declining in numbers worldwide. Not coincidentally, the earth’s ozone layer has been continuously depleted throughout the last 50 years. Atmospheric ozone blocks UV-B, a type of ultraviolet radiation that is continuously produced by the sun, and which can damage genes. Because amphibians lack hair, hide, or feathers to shield them, they are particularly vulnerable to UV-B radiation. In addition, their gelatinous eggs lack the protection of leathery or hard shells. Thus, the primary cause of the declining amphibian population is the depletion of the ozone layer.
Each of the following, if true, would strengthen the argument EXCEPT:
(A) Of the various types of radiation blocked by atmospheric ozone, UV-B is the only type that can damage genes.
(B) Amphibian populations are declining far more rapidly than are the populations of nonamphibian species whose tissues and eggs have more natural protection from UV-B.
(C) Atmospheric ozone has been significantly depleted above all the areas of the world in which amphibian populations are declining.
(D) The natural habitat of amphibians has not become smaller over the past century.
(E) Amphibian populations have declined continuously for the last 50 years.


answer is a, why not d? both a and d don't strengthen yah. Thanks!
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2栖动物减少---(不相符地)臭氧层破坏加剧---臭氧层减少UVB---(太阳)UVB破坏基因---2栖动物毛少vulnerable to UVB,,,还有个蛋
所以主要减少原因是臭氧层破坏
我个人先表个态:A 其它辐射跟加强UVB 没太大关系,并且唯不唯一不能加强soundly
D排除她因,栖息地小了,当然数量少,就不是UVB的原因了

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"D排除她因,栖息地小了,当然数量少,就不是UVB的原因了"
hehe, thanks, I haven't thought about choice d like this and thus think a and d are both irrelevent

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