Passage Set #1//Question #4

[Toby]

Hello!

I'm a bit confused about the answer to Question #4 in Lesson 8's "Passage Set #1" that is about Alzheimer's disease. I do not understand why letter E is not correct because in lines 20-22, the author claims that ApoE4 is "the maor genetic risk factor for AD." This line prompted me to choose letter E because the existence of ApoE4 appears to be the underlying reason that the amyloid theory exists.

I thought that the correct answer, letter B, was incorrect because it did not capture the underlying reason why ApoE4 was mentioned by the author. Would someone mind explaining the difference between these two answer choices please? Thanks!

Toby

[Luke Haqq]

Hi Toby!

You're right to look to lines 20-22 for keeping (E) as a contender. Indeed, (E) is true, based on the information in Passage A.

However, question 4 is specifically asking about the function/purpose that the author of Passage A uses ApoE4 for, which is a different question from the broader question about what "must be true" about ApoE4.

Given that this is a question asking us to determine the author's purpose/how a specific term functions, the best way to tackle this type of question is to contextualize the term within the broader paragraph in which it occurs. ApoE4 is discussed in the second paragraph, and the second paragraph focus on 2 new theories: (1) the amyloid hypothesis, and (2) the tau hypothesis.

The chunk of the second paragraph discussing ApoE4 (lines 20-29) is focusing on the support for the amyloid hypothesis. After discussing ApoE4, the author concludes that "many scientists offer this as evidence that beta-amyloid deposition is the initial catalyst in AD development" (lines 24-29). And that language looks much like that in the correct answer (B)--ApoE4 functions to "provide evidence that beta-amyloid deposition catalyzes Alzheimer's disease development."

Hope that helps!

[Toby]

Thanks, Luke. Your explanation definitely helped me out.