求解~新prep1-109

kenshins

109..

Though sucking zinc lozenges（菱形糖果） has been promoted as a treatment for the common cold, research has revealed no consistent effect.Recently, however, a zinc gel applied nasally has been shown to greatly reduce the duration of colds.Since the gel凝胶 contains zinc in the same form and concentration as the lozenges, the greater effectiveness of the gel must be due to the fact that cold viruses tend to concentrate in the nose, not the mouth.



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

A. Experimental subjects who used the zinc gel not only had colds of shorter duration but also had less severe symptoms than did those who used a gel that did not contain zinc.

B. The mechanism by which zinc affects the viruses that cause the common cold has not been conclusively established.


C. To make them palatable, zinc lozenges generally contain other ingredients, such as citric acid, that can interfere with the chemical activity of zinc.

D. No zinc-based cold remedy can have any effect unless it is taken or applied within 48 hours of the initial onset of cold symptoms.

E. Drug-company researchers experimenting with a nasal spray based on zinc have found that it has much the same effect on colds as the gel does.

正确答案是C,我能理解C是对的，但是不懂其他为什么不对。。

求大牛们帮忙~

rudder86

abde你都不懂？这会累死人的。具体哪个选项不懂？

xiexiang

我是这样理解的。但觉得不太对。。。
题目：
ZL可以用来治感冒，但却没有持续的效果。ZG喷剂可以减少感冒的持续时间。但zg和zl含有的Z的形态和密度都是相同的，所以ZG有效是因为感冒病毒聚集在鼻子，而不是嘴。
Which of the following, if true, most seriously weakens the argument?   C
A. Experimental subjects who used the zinc gel not only had colds of shorter duration but also had less severe symptoms than did those who used a gel that did not contain zinc. 与鼻子和嘴无关
B. The mechanism by which zinc affects the viruses that cause the common cold has not been conclusively established. 说明Z影响引起感冒的病毒的机制并没有完全建立。（无关）
C. To make them palatable, zinc lozenges generally contain other ingredients, such as citric柠檬 acid, that can interfere with the chemical activity of zinc. 不知道到底谁起的作用
D. No zinc-based cold remedy can have any effect unless it is taken or applied within 48 hours of the initial onset of cold symptoms. 与时间无关
E. Drug-company researchers experimenting with a nasal spray based on zinc have found that it has much the same effect on colds as the gel does. 对结论没作用

jingjane222

我是这样理解的。但觉得不太对。。。
题目：
ZL可以用来治感冒，但却没有持续的效果。ZG喷剂可以减少感冒的持续时间。但zg和zl含有的Z的形态和密度都是相同的，所以ZG有效是因为感冒病毒聚集在鼻子，而不是嘴。
Which of the following, if true, most seriously weakens the argument?   C
A. Experimental subjects who used the zinc gel not only had colds of shorter duration but also had less severe symptoms than did those who used a gel that did not contain zinc. 与鼻子和嘴无关 (这个是无关)
B. The mechanism by which zinc affects the viruses that cause the common cold has not been conclusively established. 说明Z影响引起感冒的病毒的机制并没有完全建立。（无关） (这个无关)
C. To make them palatable, zinc lozenges generally contain other ingredients, such as citric柠檬 acid, that can interfere with the chemical activity of zinc. 不知道到底谁起的作用 (说明口服和入鼻使用zinc比较不成立,因为口服里面有其他的东西，因此introduce 它因 可能是那个柠檬酸造成效果减弱)
D. No zinc-based cold remedy can have any effect unless it is taken or applied within 48 hours of the initial onset of cold symptoms. 与时间无关 （无关)
E. Drug-company researchers experimenting with a nasal spray based on zinc have found that it has much the same effect on colds as the gel does. 对结论没作 (首先, 重述题目条件， 其次，effect 相同，不同使用方法结果不同，其实有点儿小加强的感觉)  

然后整个题可以归纳为:-

A - a  < A - b
结论 a/=b
要weaken a/=b （A /=A)
结果C: 口服A因为柠檬酸效力/=入鼻A  introduce 他因

请各位同学指正