题目内容：

A study led by Professor Mark Weiser of Tel Aviv University and the Sheba Medical Center at Tel Hashomer Hospital has determined that young men who smoke are likely to have lower IQs than their non-smoking peers (同龄人). Tracking 18-to 21-year-old men enlisted in the Israeli army in the largest ever study of its kind, he has been able to demonstrate an important connection between the number of cigarettes young males smoke and their IQ.

The average IQ for a non-smoker was about 101, while the smokers’ average was more than seven IQ points lower, at about 94, the study determined. The IQs of young men who smoked more than a pack a day were lower still, at about 90. An IQ score in a healthy population of such young men, with no mental disorders(心理疾病), falls within the range of 84 to 116.

An addiction that doesn’t discriminate(歧视)

“In the health profession, we’ve generally thought that smokers are most likely the kind of people who have grown up in difficult neighborhoods, or who’ve been given less education at good schools,” says Weiser, whose study was reported in a recent version of the journal, Addiction, “But because our study included subjects with various socio-economic backgrounds, we’ve been able to rule out socio-economics as a major factor. The government might want to rethink how it arranges its educational resources on smoking.

Making the results more significant, the study also measured effects in twin brothers. In the case where one twin smoked, the non-smoking twin registered a higher IQ on average.

Although a lower IQ may suggest a greater risk for smoking addiction, the representing data on IQ and smoking found that most of the smokers investigated in the study had IQs within the average range, nevertheless.

In the study, researchers took data from more than 20,000 men before, during and after their time in the military. All men in the study were considered in good health, since pre-screening(筛选的)measures for suitability in the army had already been taken. The researchers found that around 28 percent of their samples smoked one or more cigarettes a day, 3 percent considered themselves ex-smokers, and 68 percent said they never smoked.

“People on the lower end of the average IQ tend to display poorer overall decision-making skills when it comes to their health,” says Weiser. He adds that his finding can help address serious concern among heath counsellors at grade and high schools.

1.The study led by Professor Mark Weiser shows that            .

A．the IQ of smoking males is lower than that of non-smokers

B．the IQ of smoking males is higher than that of non-smokers

C．the IQ of smoking males is the same as that of non-smokers

D．the IQ of smoking males is higher than that of female smokers

2.According to the passage, a smoking man’s IQ is most likely to be            .

A．101

B．94

C．80

D．120

3.What can be learned from the passage?

A．People in the military are more likely to become smokers than other people.

B．Most heavy smokers are found to have mental problems.

C．Socio-economic backgrounds have nothing to do with smoking behaviour.

D．People with lower IQs tend to be less good at controlling their addiction to smoking.

4.What is the meaning of the underlined part “An addiction that doesn’t discriminate”?

A．Smokers do not believe their IQ is affected by being addicted to smoking.

B．All people, no matter what their background, can become addicted to smoking.

C．Smoking is an addiction, and we must not discriminate against smokers.

D．The addiction to smoking is difficult to get rid of.