When the question stem is of the form,
"the author mentions ____ in order to"
"the author's reference to ____ serves to"
"the author does ___ primarily to"
the test is asking "how does this specific detail relate to the broader point/purpose of the surrounding sentences?"
I think of these as "bookend" questions, because the correct answer is almost always a paraphrase of the sentence that came before or after the specific lines/detail we're asked about.
What are the bookend ideas here?
The author had just said, in lines 16-20, that the typical educational protection in copyright law was being debateably extended to this specific case of for-profit course packs.
And after lines 23-27, the author mentions the rationale of the publishers who brought suit against the owner.
We'd like an answer that reinforces how lines 23-27 connect to either or both of these bookend ideas.
A) "demonstrate" is very harsh. The author hasn't indicated a clear opinion on the matter, now do we have any support for knowing that the owner is "exempt". In fact, the author suggests that the "typical" protection may not apply in this unique case.
B) maybe keep on first pass, since lines 23-27 do lead into the charges brought by the publishers. However, these lines don't actually explain the charges of these specific publishers. Lines 23-27 are about copyright issues in general, not this specific case. These lines bring up some legal factors that go beyond the charges brought by the publishers, so they can't be correctly said to "explain the charges".
C) This is overly opinionated, just like (A). The author has not indicated her opinion on the matter, and these lines don't indicate that the publishers' reasoning is "flawed".
D) Same as (A) and (C). The author never enters her own opinion on the matter. The author merely describes the owner's position, the publisher's position, and the court's ruling.
E) This is true. These lines do make the reader aware of what factors are considered in copyright cases. And they make the reader better enabled to comprehend the publishers' complaint in the next sentence.