一道老题，很不解，急求！

猎人92

. Birds need so much food energy tomaintain their body temperatures that some of them spend

most of their time eating. But a comparisonof a bird of a seed-eating species to a bird of a nectar-

eating species that has the same overallenergy requirement would surely show that the seed-

eating bird spends more time eating thandoes the nectar-eating bird, since a given amount of

nectar provides more energy than does thesame amount of seeds

Theargument relies on which one of the following questionable assumptions

  

(A) Birds of different species do notgenerally have the same overall energy requirements as each

other

(B) The nectar-eating bird does notsometimes also eat seeds

(C) The time it takes for the nectar-eating bird to eata given amount of nectar is not longer than the time it takes the seed-eatingbird to eat the same amount of seeds

(D) The seed-eating bird does not have alower body temperature than that of the nectar-eatingbird

(E) The overall energy requirements of agiven bird do not depend on factors such as the size of

the bird, its nest-building habits; and the climate of the region inwhich it lives

答案似乎是无争议是C, 但是我觉得还是不太明白。
因为题目说的是“因为 given amount of  nectar provides more energy than does the same amount of seeds（等量的N提供的能量大于等量的S），所以the seed-eating bird spends more time eating than does the nectar-eating bird(SB花在吃的上面的时间要多于NB花在吃的上）。
那么成立的前提确实是”SB吃饭的速度不比NB慢，也就是NB吃饭花的时间不比SB短， 可是选项C说的是NB画得时间不比NB长，这不反而削弱了吗？
请大牛解答啊！拜托了！

evelyn205205

原文的意思是这样的，因为等量的情况下，nectar提供更多的能量，吃seed的鸟要花更长的时间在吃上面，为的是获取能量。
不是你说的NB花的时间不比SB短，你的理解正好相反。
希望能帮到你。

猎人92

lw19903201 发表于 2014-2-6 04:22
c  不是说NB的时间不比SB长嘛 lz看错了??

C的意思是“NB花的时间不比SB长”，可是原题成立的assumption应该是“NB花的时间不比SB短”。。。很不解

lw19903201

c  不是说NB的时间不比SB长嘛 lz看错了??