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[Reading Comprehension]
试题详情
文章：
| Line | There are recent reports of apparently drastic |
| declines in amphibian populations and of extinctions | |
| of a number of the world’s endangered amphibian | |
| species. These declines, if real, may be signs of a | |
| (5) | general trend toward extinction, and many |
| environmentalists have claimed that immediate | |
| environmental action is necessary to remedy | |
| this “amphibian crisis,” which, in their view, is an | |
| indicator of general and catastrophic environmental | |
| (10) | degradation due to human activity. |
| To evaluate these claims, it is useful to make a | |
| preliminary distinction that is far too often ignored. | |
| A declining population should not be confused with | |
| an endangered one. An endangered population is | |
| (15) | always rare, almost always small, and, by definition, |
| under constant threat of extinction even without a | |
| proximate cause in human activities. Its disappearance, | |
| however unfortunate, should come as no great | |
| surprise. Moreover, chance events—which may | |
| (20) | indicate nothing about the direction of trends in |
| population size—may lead to its extinction. The | |
| probability of extinction due to such random factors | |
| depends on the population size and is independent of | |
| the prevailing direction of change in that size. | |
| (25) | For biologists, population declines are potentially |
| more worrisome than extinctions. Persistent | |
| declines, especially in large populations, indicate a | |
| changed ecological context. Even here, distinctions | |
| must again be made among declines that are only | |
| (30) | apparent (in the sense that they are part of habitual |
| cycles or of normal fluctuations), declines that take | |
| a population to some lower but still acceptable | |
| level, and those that threaten extinction (e.g., by | |
| taking the number of individuals below the minimum | |
| (35) | viable population). Anecdotal reports of population |
| decreases cannot distinguish among these | |
| possibilities, and some amphibian populations have | |
| shown strong fluctuations in the past. | |
| It is indisputably true that there is simply not | |
| (40) | enough long-term scientific data on amphibian |
| populations to enable researchers to identify real | |
| declines in amphibian populations. Many fairly | |
| common amphibian species declared all but extinct | |
| after severe declines in the 1950s and 1960s | |
| (45) | have subsequently recovered, and so might |
| the apparently declining populations that have | |
| generated the current appearance of an amphibian | |
| crisis. Unfortunately, long-term data will not soon | |
| be forthcoming, and postponing environmental | |
| (50) | action while we wait for it may doom species and |
| whole ecosystems to extinction. |
题目：
It can be inferred from the passage that the author believes which of the following to be true of the environmentalists mentioned in lines 5–6 ?
选项:
A、They have wrongly chosen to focus on anecdotal reports rather than on the long-term data that are currently available concerning amphibians.
B、Their recommendations are flawed because their research focuses too narrowly on a single category of animal species.
C、Their certainty that population declines in general are caused by environmental degradation is not warranted.
D、They have drawn premature conclusions concerning a crisis in amphibian populations from recent reports of declines.
E、They have overestimated the effects of chance events on trends in amphibian populations.
答案:
D
提问：
在c和d选项犹豫 最后选了c，当时是觉得premature这个词是不是用的不对。请老师解释下这两个选项区别以及如何在考场上迅速判断应该选d
解答：
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提问：
在c和d选项犹豫 最后选了c，当时是觉得premature这个词是不是用的不对。请老师解释下这两个选项区别以及如何在考场上迅速判断应该选d
解答：
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提问：
错选了C，正确答案是D。certainty is not warranted即他们的结论是有问题的。原文6-7行environmentalists have claimed that immediate environmental action is necessary to remedy中的necessary我觉得是对应certainty的。
解答：
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