I'm assuming that you are referring to question 2 in that first passage, the one about Alzheimer's Disease, GGIBA003@FIU.EDU
? If so, consider the overall tone of Passage B. The author is very concerned about AD, and the tone is pretty gloomy. The author uses words and phrases like "disturbing" (first paragraph) and "major public health concern" and "single greatest threat." (both in the second paragraph). Overall, author B paints a grim picture for our future as that population ages and more and more patients suffer from the disease. It's that tone, and words and phrases like those, that support answer D as being the Main Point. A good prephrase might be along the lines of "AD is a big and growing problem, and we better start throwing lots of money at it if we are to avoid economic disaster."
Answer B is true, but is too meek and mild to capture the dire tone of the passage. A good main point answer will convey not only the topic, but the tone and author viewpoint.
Answer C is likewise true, but is incomplete. The author thinks we need to spend money not only on a cure, but also on informing the public of effective preventive measures. And this answer also does not convey that grim tone, that sense of warning of impending doom that hangs over it all.
In short, a good Main Point answer will capture the gist of the whole passage. It won't just be a true statement about a part of the passage, and it needs to convey the tone as well as the facts.
I hope that helps!
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
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