[单项选择]

Passage One
Drunken driving--sometimes called America’s socially accepted form of murder--has become a national epidemic. Every hour of every day about three Americans on average are killed by drunken drivers, adding up an incredible 250,000 over the past decade.
A drunken driver is usually defined as one with a 0.10 blood content or roughly three beers, glasses of wine or shots of whisky drank within two hours. Heavy drinking used to be an acceptable part of the American man image and judges were tolerant in most courts, but the drunken slaughter has recently caused so many well-publicized tragedies, especially involving young children, that public opinion is no longer so tolerant.
Twenty states have raised the legal drinking age to 21, reversing a trend in the 1960s to reduce it to 18.After New Jersey lowered it to 18, the number of people killed by 18 to 20-year-old drivers more than doubled, so the state recently upped is back to 21.

A. reduced the number of convictions
B. resulted in fewer serious accidents
C. prevented bars from serving drunken customers
D. specified the amount drivers can drink