53.By analyzing the garbage of a large number of average-sized households, a group of modern urban anthropologists has found that a household discards less food the more standardized—made up of canned and prepackaged foods—its diet is. The more standardized a household’s diet is, however, the greater the quantities of fresh produce the household throws away.
Which of the following can be properly inferred from the passage?
(A) An increasing number of households rely on a highly standardized diet.
(B) The less standardized a household’s diet is, the more nonfood waste the household discards.
(C) The less standardized a household’s diet is, the smaller is the proportion of fresh produce in the household’s food waste.
(D) The less standardized a household’s diet is, the more canned and prepackaged foods the household discards as waste.
(E) The more fresh produce a household buys, the more fresh produce it throws away.
The answer is C.

the less food waste ->  the more standardized

是这样的吗，然后用逆否命题得到C？

Statements: the greater the quantities of fresh produce the household throws away这不是在说绝对数量吗？可是C在说 proportion. quantity和proportion 不是不对等的两个概念吗？

还有D选项有些迷惑。

请各位帮助。

这个题,是有点特殊的:the more standardized diets, the more fresh the house throws away;按照常理是不能够the less standardized diets, then the less.....的，因为这属于了典型的ＩＦ　Ａ，ＴＨＥＮ　Ｂ，然后在推断ＩＦ　非Ａ，ＴＨＥＮ　非Ｂ．这个就是否命题．否命题成立的条件就是两者是相互依赖变化的东西．（有点类似函数的增减）

至于ＬＳ用红色标出来的部分，是这样推的；前面还有一个推理是越多的标准化食物就有越少的dischard,现在越少的标准食物，就有更多的dischard了．同时因为家庭现在丢弃更少的新鲜食品了，分母扩大，分子减少，百分比自然就小了．

Ｄ选项是从文中推不出来的，文中只是说到了ＦＲＥＳＨ　被扔掉了的数量，没有设计扔了多少 canned and prepackaged foods ．其实文中后面那句话就只是对标准食物的解释，没有涉及到文中的具体逻辑推理的．

谢谢lizhihuantu。

您说否命题成立的条件就是两者是相互依赖变化的东西．（有点类似函数的增减）

这个对“越……越……”结构都可以成立吧。

但是对A出现推出B出现,不能运用否命题的.这点很重要哦!