题目内容：

Like many Czechs (捷克人), Lukáš Berný, 38, enjoys going out to the pub with his friends for conversation and a few beers. “I don’t drink every day,” he says. “I think about three times a week. When I go out, I usually have five to six beers at a time, about the same as my friends.” The beers are half-liters, or 500ml each.

If a half-liter of four-percent beer contains 16g of pure alcohol（酒精）, Berný and his friends are drinking 80 to 96 grams of pure alcohol on each outing. The Czech Republic’s National Institute of Public Health, however, suggests that men take in fewer than 24g of pure alcohol per day; women, fewer than 16g.

Medical experts in over 40 countries around the world have agreed that drinking “too much” can cause harm. What they can’t seem to agree upon is just how much is “too much.” National safety levels are quite different, from a limit of 10g a day in the Netherlands to Denmark’s 60g.

There are a number of reasons for this. Dr. Larry Altshuler, a medicine expert for the Cancer Treatment Centers in Tulsa, explains that while everything is based on research, “Every group, race, and gender responds to alcohol differently.”

Also, researchers aren’t using the same models or methods. He adds, “It can be like apples and oranges. How do you measure alcohol? Units, drinks, bottles or cans? What’s the alcohol content（含量）? Is it light or heavy?” While a half-liter of four percent beer contains 16g of pure alcohol, a half-liter of five percent lager contains 20g.

Constance Scharff, a director of Addiction Research at Cliffside Malibu Treatment Center in California, says she believes the reason “is largely cultural.” “But the evidence is clear that the more you drink, the more likely you are to develop alcohol-related health problems.”

1.The first paragraph is intended to ________.

A. describe the habit of Lukáš Berný

B. advise readers to live a carefree life

C. direct readers’ attention to the topic of drinking

D. support the popular belief that Czechs fancy drinking

2.The underlined word “this” in Paragraph 4 refers to ________.

A. the alcohol limit for Czechs

B. the measurement of alcohol content

C. the concern over the harmful effects of drinking

D. the difference in national safety levels of alcohol

3.According to the passage, what might determine the national safety standards of alcohol?

A. Drinking length and alcohol containers.

B. Drinking atmosphere and alcohol quality.

C. Cultural differences and measuring methods.

D. Research results and alcohol-related health problems.

4.What may be the best title for the passage?

A. How Can Drinking Be Safe?

B. How Much Alcohol Is Too Much?

C. Why Does Alcohol Do Harm to Health?

D. What Harm Will Alcohol Cause to Us?