求解释 Question:SomespeciesofArcticbirds are threatened by recent sharp increase 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 5 percent,according to official estimates.Clearly,dropping this restriction would allow the other species to recover. a.hunting limits fro 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 that 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. 请各位NN帮我分析一下这道题 非常感谢。。。 、 就是B到底说的是什么意思呢?我办老天没想出来~~~
B means hunters could not kill more than 5% of snow geese in a hunting season for many years.
The answer is B, which claims that the restriction set has no effect on the highest number of geese killed in a hunting season. Therefore, removing the restiction would not lead to more killings of the geese and better chances for the other species to recover. Thus, B weakens the argument.
In other words, what B says is that the 5% reduction in geese population due to hunting has never been reached for many years. Therefore, more than 5% reduction in geese population is unlikely to be reached even if such restriction is removed.
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 5 percent,according to official estimates.