阅读理解Doesadrinkadaykeepheartattacksaway?Overthepast20years,numerousst

阅读理解Does a drink a day keep heart attacks away? Over the past 20 years, numerous studies have found that moderate alcohol consumption, say, one or two beers, glasses of wine or cocktails daily helps to prevent coronary heart disease. Last week a report in the New England Journal of Medicine added strong new evidence in support of that theory. More important, the work provided the first solid induction (归纳) of how alcohol works to protect the heart.
In the study, researchers from Boston’s Brigham and Women’s Hospital and Harvard Medical School pared the drinking habits of 340 men and women who had suffered recent heart attack with those of healthy people of the same age and sex. The scientists found that people who sip one to three drinks a day are about half as likely to suffer heart attacks as nondrinkers are. The apparent source of the protection: those who drank alcohol had higher blood levels of high density lipoproteins, the so-called good cholesterol, which is known to prevent heart disease.
As evidence has mounted, some doctors have begun remending a daily drink for patients of heart diseases. But most physicians are not ready to remend a regular happy hour for everyone. The risks of teetotalling (绝对戒酒) are nothing pared with the dangers of too much alcohol, including high blood pressure, strokes and liver troubles—not to mention violent behaviour and traffic accidents. Moreover, some studies suggest that even  moderate drinking may increase the incidence of breast and colon cancer. Until there is evidence that the benefits of a daily dose of alcohol outweigh the risks, most people won’t be able to take a doctor’s prescription to the neighbourhood bar or liquor store.1.The medical article quoted in the first paragraph indicates ______.A.the way in which alcohol can help the heartB.how a couple of cocktails daily can stop heart problemsC.why alcoholic drinks are dangerous to one’s health 
that reports on the advantages of alcohol were misled2.Experiments showed that nondrinkers had ______.A.larger amounts of good cholesterolB.smaller amounts of good cholesterolC.higher blood pressureD.lower blood pressure3.According to the passage, moderate drinking ______.A.is remended by most doctors for heart patientsB.should be allowed on prescriptionC.is still not medically advisableD.is not related to liver problems4.The main theme of this passage is ______.A.the change in recent drinking habitsB.the connection between cancer and alcoholC.whether moderate drinkers outlive nondrinkersD.whether alcohol may be good for one’s health