og11上的2道逻辑题求助

1.       A researcher discovered that people who have low levels of immune-system activity tend to score much lower on tests of mental health than do people with normal or high immune-system activity. The researcher concluded from this experiment that the immune system protects against mental illness as well as against physical disease.

The researcher’s conclusion depends on which of the following assumptions?

C. People with high immune-system activity cannot develop mental illness.

D. Mental illness does not cause people’s immune-system activity to decrease.

答案选D。我选了C。
        题目是说的结论immune system可以保护人不得mental

和physical的病，
        所以我觉得免疫力活动旺盛的人不得病时理所当然的事情。D说得了病不会导致免疫活动力下降，不知道这个和题目有什么关系呢？

2.       Two decades after the Emerald River Dam was built, none of the 8 fish species native to the Emerald
                    River was still reproducing adequately in the river below the dam. Since the dam reduced the annual range of water temperature in the river below the dam from 50 degrees to 6 degrees, scientists have hypothesized that sharply rising water temperatures must be involved in signaling the native species to begin the reproductive cycle.

 Which of the following statements, if true, would most strengthen the scientist’s hypothesis?

A. The native fish species were still able to reproduce only in side streams of the river below the dam where the annual temperature range remains approximately 50 degrees.

这题答案就选A，我是蒙的，我不太理解原题的最后一句话，到底是说水温大幅升高是鱼类开始繁殖的信号，还是说水温升高是鱼类无法开始足量繁殖的罪魁？

就这两道，求助各位NN了，谢谢~~抱拳

第二题同意2楼的看法。

至于第一题，选项c与题目没关系，别被题目绕进去，因为我觉得我们做题的时候或多或少都会多想一些，就会想出一些不必要的东西，其实看c,就算people with high immune-system can develop mental illness又怎么样？想到这就别往下深究了，直接看d,很明显d说的整好补足了原题第一句话的一个逻辑漏洞~确定了immune-system和mentalhealth的关系，确定谁决定谁，所以看到d就是答案了，不用再深究c了，有很多这种选项就是明明与题无关，但就是选项里有几个原题中的重点词，就忽悠人拉哈哈哈~

以上是我的看法阿~哈哈，3楼说的也有理，但是我觉得逻辑题的重点不应该在某个字眼上，重在逻辑~

说的不对的多多指教阿~

太谢谢你了，我明白了

这题是assumtion的题目，没有gap，所以是not weaken的题型。 去掉weaken是因果倒置，所以是这个选项。嗯，豁然开朗~~厉害呀。谢啦

对于这个解释我还有疑惑。  range是温差对吧？温差减小（从50到8）能说明温度升高么？他的结论是，科学家认为温度上升是鱼类开始繁殖的信号。

也就是说，原文要求我们理解为range的减小是温度的升高。对吧？

可是呢，我疑惑的是，A说温差大（50°）的地方鱼类能繁殖，这不正好和结论相反么？怎么能加强呢？能不能再指点一下？谢谢哦

鱼那题我完全理解了，谢谢你哦。原来key 在sharply上。另外一道我还是很模糊。还请赐教