Which of the following, if true, most seriously weakens the reasoning?

A. Killer whales in the North Pacific usually prey on seals and sea lions but will, when this food source is scarce, seek out other prey.

B. There is no indication that substantial numbers of sea otters migrated to other locations from the North Pacific in the 1980’s.

C. Along the Pacific coast of North America in the 1980’s, sea otters were absent from many locations where they had been relatively common in former times.

D. Following the decline in the population of the sea otters, there was an increase in the population of sea urchins, which are sea otters’ main food source.

E. The North Pacific populations of seals and sea lions cover a wider geographic area than does the population of sea otters.[A]

背景-文章是说水赖的DECLINE 可能是2个原因- 吃他的鲸鱼多 或者 DISEASE （就是污染）

结论是- 是污染 ，不是因为鲸鱼！

当时我看到A 就把他排除了 因为是 我觉得他说鲸鱼会去吃其他的东西，OTHER PREY ， 我就是觉得吃OTHER ，也不一定吃水赖啊！！！

之后就看BCD E 其实看都不象 ，但是就选了E ，觉得E 是在否定 POLUTION 因为文章说是海狮海报的 POLLUTION 影响到了海赖 ， E 的意思说他们根本就不能互相影响！（其实我也觉得E不对 但还是转不过来）

我的天啊 ！PALAPALA 的打这么多 我更糊涂了！

我不知道他说的那个pollution related disease ,which could have spread to sea otters 是说！海狮的污染 造成了给海赖的污染。使海赖数量下降吗？

其实如果只是REALTED 的话 如果A 对 那不就成了A 加强了吗！海狮因为污染死了， 鲸鱼没了食物，就去吃海赖 ，SO 海赖数量少了！这就成加强了啊！

你觉得A不对的理由还是犯了MUST BE 的错误。判断是否WEAKEN的标准是问自己：该选项是否迫使作者重新考虑其观点或必须作出反应（见“考试时如何做逻辑题”）。就像该题，如果有人说了A的情况，作者必须出来澄清WALES是不吃SEA OTTERS的，否则他的观点就会受怀疑。E说的是seals and sea lions 分布较广，SEA OTTERS分布较集中。原文看不出它们活在不同水域。故无关，