Reading comp PrepTest 145 · Section 1 · Question 20

Incorrect. (Line 38; Line 41; Line 48; Line 51; Lines 55-58) Whenever the Author discusses Steele's hypothesis, she talks about what he and his adherents "believe" or "claim." She also brings up those who are skeptical of his claims, and she never herself takes sides. This answer is therefore too strongly positive in claiming that Steele has "proven" his point.

Correct. Question Type:
Main Point

Strategy Overview:
Reiterate the main point of the passage as we stated it after reading through the passage, then find the answer that is closest to it

Answer Anticipation/Relevant Lines:
The Author starts with a bit of history on evolutionary biology before stating that a modern scientist wants to revive an old theory—Lamarckism (Lines 12-16)—at least for the immune system. She then gives a rundown of how the immune system works (Paragraph 2) before using that information to present how Steele believes learned immunity can be passed down, as it would be under Lamarck's theory (Lines 41-43). The Author then presents Steele's evidence (Lines 48-55) before noting that other biologists remain skeptical (Lines 55-58). In all of this, the Author never takes sides, simply presenting the arguments.

From this, we said that the main point of the passage is:

While biologists remain skeptical, Steele and others have proposed a Lamarckian means by which learned immunity could be passed down to the next generation.

Answer Explanation:
(Lines 12-16; Lines 41-43; Lines 48-55; Lines 55-58) The Author presents the arguments of Steele and his cohort, who argue that there's a viable mechanism for acquired characteristics (in the immune system) to be passed on, thus contributing to evolution. They also claim, in the last paragraph, to have found evidence of this. While we'd like this answer better if it included a note about other biologists remaining skeptical, this answer reflects that the Author doesn't yet buy Steele's hypothesis by phrasing it as what Steele and his colleagues have "devised" and what they "claim." We'd defer on this until we read the rest, but even without the note about the skeptics, this answer still reflects the Author's feelings towards the central topic of the passage, so it's the correct answer.

Key Takeaway:
When the Author's opinion is absent from the passage, that's a very important thing to note. It will color your analysis of almost every answer choice, especially in the Main Point question and the questions from the Author's perspective. Here, there were several answers that reflected a positive or negative opinion of Steele's work that the Author simply didn't have. We were able to quickly eliminate them for this reason.

Incorrect. (Lines 14-16) Steele's claims are limited to this Lamarckian process happening in the immune system, and the Author never raises the question as to whether it operates elsewhere in the body, so this answer is out of scope.

Incorrect. (Lines 38-41; Lines 46-47) This answer is tempting, but it's ultimately incorrect for being too negative and also mischaracterizing a key difference. First, it's too negative in calling Steele's argument "highly speculative"—in the passage, the Author says that his evidence is "elegant, but speculative," missing that modifier. This answer makes it seem as if the Author is very skeptical of Steele's argument, when she never actually tips her hat. Second, this answer mischaracterizes a comparison. The answer starts by saying that it's going to point out differences between the standard theory of evolution and Steele's ("In contrast to"). However, the Author notes in Lines 46-47 that evolutionary mechanisms are all reliant on circumstantial evidence. So the fact that Steele's hypothesis relies on circumstantial evidence doesn't make it different from the standard theory, which must also rely on circumstantial evidence.

Incorrect. (Lines 14-16; Lines 55-58) This answer suggests that general Lamarckian evolution will now be accepted by the scientific population at large. However, Steele is only arguing for it in the immune system, and there isn't general acceptance of it. The Author also says that Steele hasn't shown RNA can revert to DNA in the reproductive organs—he simply believes it's possible based on a certain mechanism. Ultimately, this answer is too positive towards Steele's position, when the Author never took a side.