难易程度：★★★★
题目题材：动物，环境
gre argument 207题目：
It is known that in recent years, industrial pollution has caused the Earth's ozone layer to thin, allowing an increase in the amount of ultraviolet radiation that reaches the Earth's surface. At the same time, scientists have discovered, the population of a species of salamander that lays its eggs in mountain lakes (1) has declined. Since ultraviolet radiation is known to be damaging to delicate tissues and since salamander eggs have no protective shells, it must be the case that the increase in ultraviolet radiation has damaged many salamander eggs and prevented them from hatching(2,3). This process will no doubt cause population declines in other species, just as it has in the salamander species (4).
提纲：
(1)The scientists only studied the population of salamanders at one certain cite, thus we could not assert that the overall salamander population is declining.
(2)The author fails to compare the populations of other species of salamander whose eggs are not affected by ultraviolet radiation.
(3)The author fails to rule out other possible factors that could result in the decline in the population of the salamander species.
(4)We could not hastily generalize that other species will also be affected by the process merely based on the decline in the population of certain salamander species.
注：题目中括号里的数字表明这句话体现的是提纲中第几号缺陷。
