求助大全10-12

fei123

A study comparing a group of chronically depressed

individuals with an otherwise matched group of

individuals free from depression found significantly

more disorders of the immune system among the

depressed group. According to the researchers, these

results strongly support the hypothesis that mental

states influence the body's vulnerability to infection.

Which of the following, if true, casts the most seri-

ous doubt on the researchers' interpretation of their

findings?

(A) The researchers' view does little more than echo

a familiar theme in folklore an literature.

(B) Chronically depressed individuals are no less

careful than others to avoid exposure to

infections.

(C) Disorders of the immune system cause many of

those individuals who have them to become

chronically depressed.

(D) Individuals who have previously been free from

depression can become depressed quite

suddenly.

(E) A high frequency of infections can stem from

an unusually high level of exposure rather

than from any disorder of the immune system.

答案是C，我选的是E。不知题目是怎样推出来的？