OG173

nickynicky

173. Researchers have found that when very overweight people, who tend to have relatively low metabolic rates, lose weight primarily through dieting, their metabolisms generally remain unchanged. They will thus burn significantly fewer calories at the new weight than do people whose weight is normally at that level. Such newly thin persons will, therefore, ultimately regain weight until their body size again matches their metabolic rate.

 

The conclusion of the argument above depends on which of the following assumptions?

(A) Relatively few very overweight people who have dieted down to a new weight tend to continue to consume substantially fewer calories than do people whose normal weight is at that level.

(B) The metabolisms of people who are usually not overweight are much more able to vary than the metabolisms of people who have been very overweight.

(C) The amount of calories that a person usually burns in a day is determined more by the amount that is consumed that day than by the current weight of the individual.

(D) Researchers have not yet determined whether the metabolic rates of formerly very overweight individuals can be accelerated by means of chemical agents.
            A

(E) Because of the constancy of their metabolic rates, people who are at their usual weight normally have as much difficulty gaining weight as they do losing it.
                

The answer is A, I'm confused with B.

B如果取非， 一个人一天燃烧的卡路里是由他目前的体重决定的，不是由一天当中的食量决定的，不就weaken原文了嘛。

原文是说，哪怕一个人的体重减到这个程度了，他每天消耗的卡路里也比原来就在这个体重的人消耗的少，所以容易反弹。如果一个人消耗的卡路里的数字是由他目前的体重决定的，那么不管这个人是原来就这么重，还是刚减到这么重，他消耗的卡路里都是一样的。