Researchers took a group of teenagers who had never smoked and for one year tracked whether they took up smoking and how their mental health changed. Those who began smoking within a month of the study’s start were four times as likely to be depressed at the study’s end than those who did not begin smoking. Since nicotine in cigarettes changes brain chemistry, perhaps thereby affecting mood, it is likely that smoking contributes to depression in teenagers.

Which of the following, if true, most strengthen the argument?

A. Participants who were depressed at the study’s start were no more likely to be smokers at the study’s end than those who were not depressed.

B. Participants who began smoking within a month of the study’s start were no more likely than those who began midway through to have quit smoking by the study’s end.

C. Few, if any, of the participants in the study were friends or relatives of other participan

D. Some participants entered and emerged from a period of depression within the year of the study.

E. The researchers did not track use of alcohol by the teenagers.

Why A is correct?

做这题的时候看到A 脑子就开始短路了。

用POE 排除了其他的选项 就选了A

我觉得 结论说 吸烟导致沮丧
A说    沮丧不导致吸烟

很像排除因果倒置

好似很多类似的题

不知道这么想对不对 待指点