[求助]诚心请教Ｌ－１－１－１８；Ｌ－１－１－２４

；[求助]诚心请教Ｌ－１－１－１８；Ｌ－１－１－２４

１８：

18.   Brushing your teeth regularly, no matter which toothpaste you use, will reduce your chances of tooth decay. Scientists have concluded that, when you brush, you reduce tooth decay by removing the film of plaque that forms on teeth and gums. So, you can forget about fluorides: brush your teeth carefully and say goodbye to cavities.

Which one of the following is a criticism of the reasoning in the argument?

(A) Brushing with fluoride toothpaste has been shown to reduce tooth decay.

(B) The fact that brushing will reduce tooth decay does not show that fluorides are of no value.

(C) Few people adequately remove plaque by brushing.

(D) People have plaque on their teeth most of the time.（B）

(E) Scientists have been wrong about fluorides.

请问这题应该怎样想？Ｃ和其他选项为什么不对？

２４：

24.   An unbiased observer of everyday encounters in Western societies would surely not find many instances of unkindness by people under 65 toward people over 65. There are undoubtedly incidents of unkindness based on age, and these warrant reproof. However, the very fact that such reproof occurs and is generally accepted implies that our Western societies basically respect the elderly. The same conclusion can be drawn from a recent survey finding: 71 percent of the under 65 population agreed with the statement that “people over 65 receive too little respect from society”, while only 44 percent of the over-65 population, the target of the alleged irreverence agreed with it.

The author concludes that Western societies basically respect the elderly partly because

(A) people under 65 are just as kind to people over 65 as they are to people of their own age group

(B) survey data suggest that fewer people over 65 than under 65 get too little respect

(C) disrespect for the elderly does not go so far as to result in actual harm

(D) survey data suggest that people over 65 are more aware of incidents involving disrespect to the elderly than are people under 65（E）

(E) incidents of unkindness to the elderly are neither common nor generally accepted in Western societies

看过原来的讨论帖，但还不是很明白，请问Ｃ为什么错呢？非常感谢！

Q18: Which one of the following is a criticism of the reasoning in the argument?

Note:  This question requires you to undermine the 'reasoning' .(reasoning: the process of thinking about things in a logical way)

Q19: 'Actual harm' is a new conception, which is not mentioned in the stem.