问一道weaken的题

zijing4546

    

Although migraine headaches are
believed to be caused by food allergies, putting patients on diets that eliminate
those foods to which the patients have been demonstrated to have allergic
migraine reactions frequently does not stop headaches. Obviously, some other
cause of migraine headaches besides food allergies much exist.

    

Which of the following, if true, would
most weaken the conclusion above?

    

(A) Many common foods elicit an
allergic response only after several days, making it very difficult to observe links
between specific foods patients eat and headaches they develop.

    

(B) Food allergies affect many people
who never develop the symptom of migraine headaches.

    

(C) Many patients report that the
foods that cause them migraine headaches are among the foods that they most
enjoy eating.

    

(D) Very few patients have allergic
migraine reactions as children live migraine-free adult lives once they have eliminated
from their diets foods to which they have been demonstrated to be allergic.

    (E) Very rarely do food allergies cause patients
to suffer a symptom more severe than that of migraine headaches.


这道题我蒙对了,(A), 但是逻辑关系我不是很清楚,想请大家帮忙分析一下这道题的思路,以及各选项的优劣,谢谢

lg77xx

Although migraine headaches are believed to be caused by food allergies, putting patients on diets that eliminate those foods to which the patients have been demonstrated to have allergic migraine reactions frequently does not stop headaches. Obviously, some other cause of migraine headaches besides food allergies much exist.

Which of the following, if true, would most weaken the conclusion above?

(A) Many common foods elicit an allergic response only after several days, making it very difficult to observe links between specific foods patients eat and headaches they develop. 他因削弱，说并不是由于存在其他原因，而是由于eliminate those foods中对foods选择的不准确。

(B) Food allergies affect many people who never develop the symptom of migraine headaches. 无关，没有提到导致头痛的Some other cause。

(C) Many patients report that the foods that cause them migraine headaches are among the foods that they most enjoy eating. 已经消除的东西，就算再enjoy也不会导致头痛啊，在题目前提以外。

(D) Very few patients have allergic migraine reactions as children live migraine-free adult lives once they have eliminated from their diets foods to which they have been demonstrated to be allergic.

(E) Very rarely do food allergies cause patients to suffer a symptom more severe than that of migraine headaches. 比较对象不存在

[此贴子已经被作者于2007-3-10 8:49:57编辑过]

zijing4546

非常感谢~~~~~~~~~~~~~