I'd like to offer another consideration.
While the fact that the argument doesn't mention "only" is one of the reasons its wrong, the essence of the argument is the
jump Susan makes in justifying testing of ordinary products on the
SAME grounds as she justifies experimentation for cure of ailments. Say we removed the word
"Only" Revised option:
- Her claim that animal experimentation is justifiable if it supports human values contradicts her claim that such experimentation is justifiable if it leads to cures for human ailments.
IMO this still doesn't make this option a correct choice!
"animal suffering is unfortunate, it is justifiable if it can lead to cures for human ailments" - this claim IMO, as suggested in this option,
is NOT contradicted by the claim " animal experimentation is justifiable if it supports human values " This is because, the latter could also have been a "sufficient" condition
independent of this justification. It
isn't necessary for experimentation to be justified by its ability to cure ailments

but yes its
sufficient.The flaw as I mentioned earlier, is her
justifying experimentation of
consumer products on the
same grounds
without establishing how it is curing ailments/preserving human life. This is of course tackled by E
KarishmaB
Bunuel
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) She fails to show how mere support for human values actually preserves human lives.
Responding to a pm:
(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 does not claim that "experimentation is justifiable ONLY IF it leads to cures for human ailments."
She says "it is justifiable IF it can lead to cures for human ailments."
So she gives a sufficient condition, not a necessary one. So this is not a part of her argument so it cannot be the flaw in her argument.
(B) She places a higher value on human cleanliness, convenience, and beauty than she does on the preservation of animal life.Our values and ethos are our own. We cannot call one group's values flaws.
(C) She uses the word “value” in two different senses.She does use the word "value" in two different senses. The word "value" can be logically used in both senses. That is not a flaw.
"They don't value human life" and "These are worthwhile human values" and two different uses of the word and both are justified in the way they are used. There is nothing wrong or ambiguous here.
(D) She assumes that all ordinary consumer products aid in the preservation of human life.She does not assume so in her argument. Nowhere does she imply that consumer products aid in the preservation of human life.
(E) She fails to show how mere support for human values actually preserves human lives.Correct.
Her argument is that "Those who oppose experimentation on animals do not properly value the preservation of human life" and "These experiments are justifiable on the same grounds, since cleanliness, convenience, and beauty are worthwhile human values deserving of support." When she says that "these experiments are justifiable on the same grounds," she needs to extend her argument to show how it ties up with "preservation of human life" aspect such as
Without cleanliness, humans are prone to life threatening diseases or something similar. She needed to tie the human values to "preservation of human life" for her argument to make sense.
Answer (E)
Here are some discussions on method questions: