【请教GWD 一道逻辑题的答案~】

水色青空

Q37: TTGWD4-Q11:
Because ethylene dibromide, a chemical used to fumigate grain, was blamed for the high rate of nerve damage suffered by people who work in grain-processing plants, many such plants switched to other chemical fumigants two years ago.  Since then, however, the percentage of workers at these plants who were newly diagnosed with nerve damage has not dropped significantly.  Therefore, either ethylene dibromide was wrongly blamed or else the new chemicals also cause nerve damage.
Which of the following is an assumption on which the argument depends?
A. If the new chemicals cause nerve damage, the nerve damage caused would be different from any nerve damage that ethylene dibromide may cause.
B. There are no chemical fumigants that are completely safe for workers in grain-processing plants.
C. If ethylene dibromide causes nerve damage, it does not take two years or longer for that damage to become detectable.
D. Workers at grain-processing plants typically continue to work there even after being diagnosed with nerve damage.
E. Workers at grain-processing plants that still use ethylene dibromide continue to have a high rate of nerve damage.











这题目选的是C，我在BC中犹豫了很久.....用的是取非后削弱文章来做，B选项说有一种化学物质能对人类完全无伤害，这不是削弱了文章的结论：不是错误的认为ed有问题就是新的化学物质也能引起疾病 吗？ 感觉B削弱了后一个部分（新的化学物质也能引起疾病），而C削弱了前一部分（错误的认为ed有问题），实在不明白要怎么排除？？请求帮忙谢谢！~~~

水色青空

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水色青空

up~~

水色青空

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jhhuzhle

饿 直接看C选项吧。。。 挺直接的。说是建立在 这种神经损伤两年就能观察出来  这个假设上。   否则 这个结论就不成立 。。。比较明显。。
其他选项就无视了。。。。