114. The number of North American children who are obese-that is, who have more body fat than do 85 percent of North American children their age---is steadily increasing, according to four major studies conducted over the past 15 years.
If the finding reported above is correct, it can be properly concluded that
A. when four majors studies all produce similar results, those studies must be accurate
B. North American children have been progressively less physically active over the past 15 years
C. the number of North American children who are not obese increased over the past 15 years
D. over the past 15 years, the number of North American children who are underweight has declined
E. the incidence of obesity in North American children tends to increase as the children grow older
本题的答案是C， 我知道别的答案更糟糕，可是如果说是C （没有肥胖的孩子增加了在过去的15年）我想问问是孩子的总数增加了，（增加的人中肥胖的和没有肥胖的都增加了，或者只是没有肥胖的孩子增加了） 还是说总数没有增加 （是那些原来肥胖的孩子便瘦了）呢？
这样就有三种情况了啊，不同的情况得出的结果不同啊。
如果是说原来的有些肥胖的孩子变瘦了，那么总体的体重就会下降， 有可能 children who have more body fat than do 85 percent of North American children their age---is steadily increasing， 但是也有可能下降啊。
我现在真的是晕了
反过来想
体重超过整个北美85%的孩子才叫胖子
如果大家都是胖子，那么超过这个值的人真是少之又少，他们将不再归为胖子
为了让胖子凸显出来，必须增加瘦子的数量，这也超过这个值的人数才能持续的增加
所以是C
er。。。版主都是NN。。。我是小菜鸟一只～
那要超过85%才是肥胖，也就是说85%的儿童是normal，那剩下的15%就是超重。那按照基本的计算公式来说，这个肥胖的总人数，是等于儿童的总人数*那个percent，那么由于15%和85%是两个恒定的比率，所以就是总人数上升啦，所以非肥胖的人数也上升。个人乱七八糟的浅见
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