标题: GWD17-Q11 [打印本页] 作者: aj_goodnews 时间: 2010-7-22 21:37 标题: GWD17-Q11 Some species of Arctic birds are threatened by recent sharp increases in the population of snow geese, which breed in the Arctic and are displacing birds of less vigorous species. Although snow geese are a popular quarry for hunters in the southern regions where they winter, the hunting season ends if and when hunting has reduced the population by five percent, according to official estimates. Clearly, dropping this restriction would allow the other species to recover.
Which of the following, if true, most seriously undermines the argument?
A. Hunting limits for snow geese were imposed many years ago in response to a sharp decline in the population of snow geese. B. It has been many years since the restriction led to the hunting season for snow geese being closed earlier than the scheduled date. C. The number of snow geese taken by hunters each year has grown every year for several years. D. As their population has increased, snow geese have recolonized wintering grounds that they had not used for several seasons. E. In the snow goose’s winter habitats, the goose faces no significant natural predation.
The answer is B.
Can someone explain why B is the right one.
Most of the explanations in the posts are saying that B tells us the 5% restriction never be reached by hunters so that the dropping the restriction will have no effect on population of geese.
However in my opinion I think B tells us that the only reason why the hunting season ends earlier is that 5% decrease has been reached earlier already before the scheduled date, instead of that the restriction can not be reached.
Can someone clarify the reasoning?作者: loverwy 时间: 2010-7-24 13:09
文章第一句话“Some species of Arctic birds are threatened by recent sharp increases in the population of snow geese”，可以暗示之前几年, snow geese的数量并不是很多