15. Susan: Those who oppose experimentation on animals do not properly value the preservation of human life. Although animal suffering is unfortunate, it is justifiable if it can lead to cures for human ailments.

Melvin: But much animal experimentation involves testing of ordinary consumer products such as soaps, dyes, and cosmetics.

Susan: These experiments are justifiable on the same grounds, since cleanliness, convenience, and beauty are worthwhile human values deserving of support.

Which of the following is the best statement of the logical flaw in Susan’s argument?

(A) Her claim that animal experimentation is justifiable if it supports human values contradicts her claim that such experimentation is justifiable only if it leads to cures for human ailments.

(B) She places a higher value on human cleanliness, convenience, and beauty than she does on the preservation of animal life.

(C) She uses the word “value” in two different senses.

(D) She assumes that all ordinary consumer products aid in the preservation of human life.（E）

(E) She fails to show how mere support for human values actually preserves human lives.

没人问过这到题。我选的C，我觉得一个是value是指生命，后一个指的是其他的。

看了答案，觉得E似乎也可以，但我做题的时候，一定不会想到选它。

另外D，错的原因是"all”吗？

请大家指导思路一下，谢谢了

“do not properly value the preservation of human life”中的value是动词，指重视。

“are worthwhile human values”中的values是名词，指价值。

A指出了部分问题，即susan提出了2个论证，但是问题是我们看不出这2者必然有矛盾。

E指出了症结：虽然susan的2个论证没有明显自相矛盾，但是，她没有指出这2者有何内在关系。这正是她需要做的，否则，她的论证就不严密：别人会攻击她的论证是双重标准。

她从来没有说B和D， 而且D太强了。

她确实说了C，但那不是问题的关键