Critical Reasoning

The publisher of a best-selling self-help book had, in some promotional material, claimed that it showed readers how to become exceptionally successful. Of course everyone knows that no book can deliver to the many what by definition, must remain limited to the few exceptional success. Thus although it is clear that the publisher knowingly made a false claim. doing so should not be considered unethical in this case.

Which one of the following principles if valid most strongly supports the reasoning above?

(A) Knowingly making a false claim is unethical only if it is reasonable for people to accept the claim as true.

(B) Knowingly making a false claim is unethical if those making it derive a gain at the expense of those acting as if the claim were true.

(C) Knowingly making a false claim is unethical in only those cases in which those who accept the claim as true suffer a hardship greater than the gain they were anticipating.

(D) Knowingly making a false claim is unethical only if there is a possibility that someone will act as if the claim might be true.

(E) Knowingly making a false claim is unethical in at least those cases in which for someone else to discover that the claim is false that person must have acted as if the claim were true.

[spoiler]OA: (A)[/spoiler]
[spoiler]LSAT [LR][PT24-S3-Q25][/spoiler]

I notice there is a conditional relationship in the answer, but I am confused whether the conclusion represents the same relationship as well. (i.e., does although..., ... equal ....only if.....?)

(Maybe the answer is clear enough without conditional relationship in mind.)