"The greatness of individuals can be decided only by those who live after them, not by their contemporaries."
个体的伟大只能由他/她的后人来评判，而不能由他/她同时代的人来评判。
Argument：
The following is a letter to the editor of an environmental magazine.
"Two studies of amphibians in Xanadu National Park confirm a significant decline in the numbers of amphibians. In 1975 there were seven species of amphibians in the park, and there were abundant numbers of each species. However, in 2002 only four species of amphibians were observed in the park, and the numbers of each species were drastically reduced. One proposed explanation is that the decline was caused by the introduction of trout into the park's waters, which began in 1975. (Trout are known to eat amphibian eggs.)"
在X国家公园对于两栖动物所进行的两次研究证实了两栖动物数量的急剧下降。1975年公园中有7种两栖动物，每种的数量都很丰富。 然而到了202年在公园中只观察到4种两栖动物，并且每种动物的数量都显著下降。一种解释就是两栖动物数量的下降曾被归因于始于1975年的在公园水域引入鲑鱼的行为(鲑鱼捕食两栖动物的卵)。
Write a response in which you discuss one or more alternative explanations that could rival the proposed explanation and explain how your explanation(s) can plausibly account for the facts presented in the argument.
