CR OG Diagnostic-CR26

sagamba

Guillemots are birds of Arctic Regions. They feed on fish that gather beneath thin sheets of floating ice, and they nest on nearby land. Guillemots need 80 consecutive snow-free days in a year to raise their chicks, so until average temperatures in the Arctic began to rice recently, the guillemots' range was limited to the southernmost Arctic coast. Therefore, if the warming continues, the guillemots' range will probably be enlarged by being extended northward along the coast.

Which of the following, if true, most seriously weakens the argument?
A. Even when the warming trend continues, there will still be years in which guillemot chicks are killed by an unusually early snow.
B. If the Arctic warming continues, guillemots' current predators are likely to succeed in extending their own range farther north.
C. Guillemots nest in coastal areas, where temperatures are generally high than inland areas.
D. If the Arctic warming continues, much of the thin ice in the southern Arctic will disappear.
E. The fist that guillemots eat are currently preyed on by a wilder variety of predators in the southernmost Arctic regions than they are farther north.

Ans: D

倒是选对了,用的是排除法. 但我选择时, 假设 如果冰没了,就捉不到鱼了.可现在仔细想想,这个不是文章里面的内容. GMAT不都要按照文章的内容么.

请问我哪里有想错?

endless1990

结论是 the guillemots'  RANGE will probably be ENLARGED by being extended northward along the coast


D中是说southern 那的冰没有了，所以guillemots的北迁是整体移动，而不是扩散，就相当于 一张白纸上面放了一个圆环， 圆环从左边拿到右边而已，圆环自己并没有变大---range be enlarged

sagamba

谢谢解释，可是我没大看懂。
我同意 结论是： the guillemots'  RANGE will probably be ENLARGED by being extended northward along the coast
D 是直接反对： the guillemots’ move northward would not enlarge their range if they lost their food source, fish found under thin ice, in the
southern Arctic. （我的理解是没吃的了，就不扩张领地了）
我是 假设 thin ice disappear 会导致 他们没鱼吃。 不过我们可以在GMAT  中这么假设么？

philipyu1025

我觉得可以这么假设诶。。因为明显说了啊，他们吃的鱼就在ice下面，没了ice不就没了鱼吗？