lsat 5-2-8

nina_nn

Although nondairy coffee lighteners made with coconut oil contain 2 grams of saturated fat per tablespoon, or 7 times more than does whole milk, those lighteners usually contain no cholesterol. Yet one tablespoon of such lighteners causes the consumer’s blood cholesterol to rise to a higher level than does an identical amount of whole milk, which contains 2 milligrams of cholesterol per tablespoon.

8.     Which one of the following, if true, contributes most to an explanation of the apparent discrepancy noted above?

(A) Nutritionists recommend that adults consume as little saturated fat as possible and no more than 250 milligrams of cholesterol a day.

(B) One gram of saturated fat in food has roughly the same effect on blood cholesterol as 25 milligrams of cholesterol in food.

(C) Light cream, a dairy product that contains 5 times more cholesterol than does whole milk, is often chosen as a lightener by consumers who normally prefer whole milk.

(D) Certain nondairy coffee lighteners made without coconut oil contain less saturated fat and less cholesterol than does whole milk.

(E) The lower the saturated fat content of dairy products, the less cholesterol they usually contain.

 

答案是B,为什么呢？题目什么意思？ 数是怎么推算出的？

templar

题目的意思是：

制作每片 coffee lightener 所需的 coconut oil 含有 2 gram saturated fat (是牛奶的7倍)，基本no cholesterol （牛奶有cholesterol）。
但是服用一片 coffee lighterner 后人的blood cholesterol会提高到比服用含有2 milligrams cholesterol牛奶后更高的水平。

问为什么？

解题思路：要能解释为什么不含cholesterol的coffee lightener 会比 含cholesterol的牛奶 更能提高人的blood cholesterol

A) 营养学家建议。。。。。。。
与我们要找的无关。因为这里说的XX人的建议，而我们要找的是facts，能解释这个问题的facts。排除

B) 1 gram saturated fat 对blood cholesterol 的作用基本等于25 milligrams cholesterol 的作用。
是facts，符合我们要找的方向。再看，1 gram saturated = 25 milligrams cholesterol，题目里说coffee lightener有2gram saturated fat，那么就= 25 x 2 = 50 milligram cholesterol 的作用。同时，牛奶只含有2 milligrams cholesterol。
这就能解释为什么coffee lightener 比milk 提高更多的blood cholesterol

C) Light cream, xxxxx(定语从句，起描述作用，可忽略), 经常被用来。。。。
看到这里，就了解了讲的是某种无关物品的使用习惯，与我们要找的方向不符，排除掉。

D) 某些不含coconut oil的nondairy coffee lightnener。。。。。。
看到这里，发现所讲的与题目讨论的 含coconut oil的coffee lightener是不同的东西，不在讨论范围之内，当然也就不能解释问题。排除掉。

E) dairy products所含saturated fat 越低，其cholesterol就越少。
本来题目里的问题就是“不含cholesterol的coffee lightener 会比 含cholesterol的牛奶 更能提高人的blood cholestero”，这个选项只是再次强调前者的cholesterol 少，文不对题的回答。

所以选B

其实谈不上什么逻辑，很多选项根本就没在回答问题，快速排除掉就行了。

[此贴子已经被作者于2007-3-10 1:40:44编辑过]

nina_nn

明白了~~谢谢！