洛基狗! PREP原题! 答案求解释!

cutewen

新PREP1：95. (28538-!-item-!-188;#058&002980)感谢liber00000提醒

Which of the following most logically completes the passage?

Using new detection techniques, researchers have found trace amounts of various medicinal substances in lakes and rivers.Taken in large quantities, these substances could have serious health effects, but they are present in quantities far too low to cause any physiological response in people who drink the water or bathe in it.Nevertheless, medical experts contend that eliminating these trace amounts from the water will have public health benefits, since __________.

A. some of the medicinal substances found in lakes and rivers are harmless to humans even if taken in large quantities

B. some of the medicinal substances found in lakes and rivers can counteract possible harmful effects of other such substances found there

C. people who develop undesirable side effects when being treated with medicines that contain these substances generally have their treatment changed

D. most medicinal substances that reach lakes or rivers rapidly break down into harmless substances

E. disease-causing bacteria exposed to low concentrations of certain medicinal substances can become resistant to them（Answer）



有人能解释一下E为什么是对的吗。  B又为何不对呢？

谢谢大家!

ameliewoo

LZ B 的意思是说，在水里，那些药可以抵消别的物质的一些坏作用，这不是和题目要的意思相反嘛？？所以排除
E的意思是虽然药在水里的含量很少，但是细菌暴露在如此少的药里，也会产生抗药性~~~所以才要去除水里的药成分~~

cutewen

LS的 谢谢回答! 只是我觉得E里面说的  产生抗药性 是抗的 那些水中有害的物质啊。

是不是我句子理解有偏差？

sdcar2010

LS的 谢谢回答! 只是我觉得E里面说的  产生抗药性 是抗的 那些水中有害的物质啊。

是不是我句子理解有偏差？

-- by 会员 cutewen (2010/11/4 23:39:46)

Your correctly understand the meaning of answer E, but you failed to infer properly the consequence of the meaning thereif. If bacteria acquired drug-resistance, then in the future patients infected by such bacteria would have a harder time to find cure.  Thus, this would cause future problems to public health.