单选题 Spiders of many species change color to match the pigmentation of the flowers they sit on. The insects preyed on by those spiders, unlike human beings, possess color discrimination so acute that they can readily see the spiders despite the seeming camouflage. Clearly, then, it must be in evading their own predators that the spiders' color changes are useful to them.
Which of the following, if tree, most strengthens the argument?

A、 Among the animals that feed on color-changing spiders are a few species of bat, which find their prey through sound echoes.
B、 Certain animals that feed on color-changing spiders do so only sparingly in order to keep from ingesting harmful amounts of spider venom.
C、 Color-changing spiders possess color discrimination that is more acute than that of spiders that lack the ability to change color.
D、 Color-changing spiders spin webs that are readily seen by the predators of those spiders.
E、 (E) The color discrimination of certain birds that feed on color-changing spiders is no more acute than that of human beings.

【正确答案】 E

【答案解析】[解析] 本题逻辑推理难度并不大，难主要难在阅读上，尤其是许多考生不能精确理解最后一句话的含义。本句是强调句型，其正常语序应为，“The spiders' color changes are useful to them in evading their own predactors”，即蜘蛛颜色改变对它们本身的用处在于躲避自己的天敌，所以(E)选项支持了上面的结论。因为本题段落中已指出人类颜色鉴别能力差，而鸟类比人类更为逊色，因此就最好地支持蜘蛛改变颜色确实是躲避自己的捕食者。