The higher the level of certain vitamins and minerals in the bloodstream, the better a person's lung function, as measured by the amount of air the person can expel in one second. The lung function of smokers is significantly worse, on average, than that of nonsmokers. Clearly, therefore, one way for smokers to improve their lung function is for them to increase their intake of foods that are rich in these helpful vitamins and minerals.
Which of the following is an assumption on which this argument depends?
(A) Smokers are less likely than nonsmokers to have diets that are rich in vitamins and minerals.
(E) Smoking does not introduce into the body chemicals that prevent the helpful vitamins and minerals from entering the bloodstream.
文说：vitamins and minerals 正相关肺功能。吸烟降低肺功能。
结论：增加吸烟者食物中vitamins and minerals 能提高他们肺功能。
（吸烟和vitamins and minerals 无明确逻辑连接，需要假设架桥）
A 虽然涉及吸烟者less 。。。vitamins and minerals的意思，但一个关键地方限制是在 have diets 方面，这个假设感觉和E相比就更远了，这里如成立，又需要一个限制假设 影响vitamins and minerals 的只有 diets。
E not+削弱模式。去掉not看就明白了。
(D) Stopping smoking will not typically improve lung function more than any diet changes can.
D为什么不对啊？好像没人选D ，但是我将D取非，不就是停止吸烟比改善饮食习惯更能改善肺功能。
排除了削弱原文的一种情况：给出它因-停止吸烟可以更好地改善肺功能作者: emmahsu 时间: 2011-10-11 06:19
