单选题 A 20 percent decline in lobster catches in Maine waters since 1980 can be justifiably blamed on legislation passed in 1972 to protect harbor seals. Maine"s population of harbor seals is now double the level existing before protection was initiated, and these seals are known to eat both fish and lobsters.
Which of the following, if tree, would most seriously weaken the argument above?

A、 Harbor seals usually eat more fish than lobsters, but the seals are natural predators of both
B、 Although harbor seals are skillful predators of lobsters, they rarely finish eating their catch
C、 Harbor seals attract tourists to Maine"s coastal areas, thus revitalizing the local economy
D、 Authors of the 1972 legislation protecting harbor seals were convinced that an increase in that animal"s numbers would not have a measurably negative impact on the lobster catch
E、 The record lobster harvests of the late 1970"s removed large numbers of mature lobsters from the reproductive stock

【正确答案】 E

【答案解析】[解析] 本题推理为“就现象提出解释”，一般暗含这种解释是惟一的原因，反对思路是“有他因”。(E)很好地实现了问题目的，所以(E)正确；(D)易误选，但(D)中的“相信”与“事实”是两码事，因此(D)起不到任何作用。