Q37:
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 strengthens 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
participants.
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. 大家帮我看看呀，我第一句话看不是太懂，特别是那些likely to , 又加上什么no more likely to 看到这些我就犯晕呀，能否帮忙解释下呢？谢谢 | 
