Susan: Those who oppose experimentation on animals do not properly val

Pre-thinking:

Susan points out that animal suffering is an unfortunate necessity in the pursuit to save human lives and cure human ailments. Melvin counters that, on the other hand, much of experimentation involves testing of ordinary consumer products such as soaps, dyes, and cosmetics. Susan replies that this too is justified on the same grounds since cleanliness, convenience, and beauty are worthwhile human values.

Straightaway we can notice a language shift in the argument. While initially Susan justifies animal suffering quoting the saving of human lives, later on she only puts forth "worthwhile human values". Therefore the connection between "worthwhile human values" and "saving human lives" is not made out clearly.

Let us examine the answer options.

(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. She doesn't claim that such experimentation is justifiable only if it leads to cures for human ailments. Eliminate.

(B) She places a higher value on human cleanliness, convenience, and beauty than she does on the preservation of animal life. While this is true, it cannot be treated as a "logical" flaw, which is what the question asks us to locate. Eliminate.

(C) She uses the word “value” in two different senses. Same as (B). Eliminate.

(D) She assumes that all ordinary consumer products aid in the preservation of human life. She does not make any such assumption in her argument. Eliminate.

(E) She fails to show how mere support for human values actually preserves human lives. Correct answer and consistent with our pre-thinking.

Hope this helps.