FeiFei-58

58. Some people say that the scarcity of food is a function of the finite limits of the earth’s resources, coupled with a relentless rate of population growth. This analysis fails to recognize, however, that much of the world’s agricultural resources are used to feed livestock instead of people. In the United States, for example, almost one-half of the agricultural acreage is devoted to crops fed to livestock. A steer reduces twenty-one pounds of inexpensive grain to one pound of expensive meat. Thus, the scarcity of food is not merely a function of limited resources and population growth.

Which one of the following is an assumption that would allow the conclusion in the argument to be properly drawn?

A.        People prefer eating meat to eating grain.

B.        Meat is twenty-one times more expensive than grain.

C.        The limits of the earth’s agricultural resources are not finite.

D.       More than one-half of the agricultural acreage in the United States is devoted to drops fed to humans.

E.        Growing crops for human consumption on the acreage currently devoted to crops for livestock will yield more food for more people.

the answer is E, i am totally confused...

结论是: Thus, the scarcity of food is not merely a function of limited resources and population growth.

等于 there are other reasons to contribute the scarcity, 通过文章可知, 值得是that much of the world’s agricultural resources are used to feed livestock instead of people.

假设是让the other reason成立, 如果E不成立,牲畜占的资源不能转化成人的食物,则the other reason不成立 ,所以E构成了一个必要条件.

谢谢楼上

但我还是不明白。结论是the scarcity of food is not merely a function of limited resources and population growth。所以为了让这个结论能够PROPERLY DRAWN。也就是说让结论成立，那我们的假设是应该让THE OTHER REASON成立才对啊？

原文逻辑：因为有多余的土地去种喂牲畜的庄稼， 所以土地有限不是理由（即还有其他理由）

如果这些牲畜构成的食物多于这些土地直接种供人类吃的食物，这说明这些土地没浪费，土地还是有限，还是缺食物的理由。E选项排出这种可能性

我懂了。我同意2楼的意见。

结论是，resource limit和increasing population不是food scarcity唯一的理由，还有一个理由就是too much food being used to feed livestocks.

如果要证明最后一条也是导致食物短缺的理由，必须证明没有了它，食物就不会紧张。所以必须有一个assumption说明这点。这就是Growing crops for human consumption on the acreage currently devoted to crops for livestock will yield more food for more people.

谢谢大家！茅塞顿开。

还是不太明白

E. Growing crops for human consumption on the acreage currently devoted to crops for livestock will yield more food for more people.

这里的more是指和什么比较？

求救啊！

feifei里的解释如下，可我看不懂为何要“反驳”（红字部分）

E is the best answer. 喂养牲畜消耗的粮食为人们创造更多的食物。（题目内容是：有观点认为食物缺乏是因为土地资源有限而人口数量却不断增多。但作者认为该观点忽视了农产品中有相当大一部分是用来喂家畜的。在美国几乎有一半土地的粮食是为了养家畜。1磅肉要用去21磅廉价的谷物。因此，食物缺乏不仅是因为土地资源有限而人口数量却不断增多。）根据题目要求，我们只须反驳养家畜对粮食紧缺造成的影响。

lawyer_1 的解释如下：可我看不懂E选项为何是“排除”（红字部分），E不是指出这种可能性吗？我第一次做的时候也错了，是不是给绕昏了！

原文逻辑：因为有多余的土地去种喂牲畜的庄稼， 所以土地有限不是理由（即还有其他理由）

如果这些牲畜构成的食物多于这些土地直接种供人类吃的食物，这说明这些土地没浪费，土地还是有限，还是缺食物的理由。E选项排出这种可能性

原文逻辑：因为有多余的土地去种喂牲畜的庄稼， 所以土地有限不是理由（即还有其他理由）

如果这些牲畜构成的食物多于这些土地直接种供人类吃的食物，这说明这些土地没浪费，土地还是有限，还是缺食物的理由。E选项排出这种可能性

feifei里面对E的解释有问题，因该是“如果用现在养牲畜的地改种粮食的话，可以给人类提供更多的食物。”
这样就清楚了。

大家对于E选项的意思可能给误导了，arcsun说的才是正确的意思。

这样我就理解了，谢谢！