PrepTest 157, Section 3, Question 11
Biologist: The evolutionary advantage of sexual reproduction is(70 more words not shown)
The claim that an increased(28 more words not shown)
- AIt is a(8 more words not shown)
- BIt is presented(11 more words not shown)
- CIt is a(10 more words not shown)
- DIt describes an(9 more words not shown)
- EIt is presented(11 more words not shown)
Reading the argument
The biologist separates what benefits a species from what benefits an individual. Follow that distinction through the argument.
The first claim is that sexual reproduction creates a wider range of genetic variation, which helps the species as a whole. The next claim denies that this greater range benefits any individual member. Accept those as the biologist's starting points for the purpose of understanding the reasoning. The author then concludes that selection favoring some entire species over others is the sole reason sexual reproduction became so common.
In the author's picture, imagine comparing a species with this reproductive advantage with a species without it. The explanation for the first species' success would concern an advantage at the species level. The claim about individuals helps the author steer away from an explanation based on individual advantage.
What we’re looking for
We're asked about that claim's role. Work backward from the final conclusion: why does the biologist point to selection among species? Because the supposed benefit helps the species, not its individual members. So the statement is being used as support. Identifying that use doesn't require us to endorse the biological account or agree that the conclusion's “sole reason” has been proved.
Working the answers
- ACorrect
The denial of an individual advantage helps support the conclusion that the explanation lies in natural selection favoring entire species. It is one of the claims the author reasons from. That's what it means to call a statement a premise.
- B
The biologist isn't presenting this claim as a reason to doubt the conclusion. It points in the direction the author wants to go: away from an individual benefit and toward a species-level explanation. Support and doubt play opposite roles here.
- C
The argument never tries to show that increased variation actually does benefit individual members. The author accepts the claim and uses it. A claim being challenged would instead be something the later reasoning tried to disprove.
- D
What the author seeks to explain is why sexual reproduction became the rule among animals and plants. The targeted statement isn't that phenomenon. It's part of the evidence used to explain it. Ask what the argument's “why” question is about, rather than treating every statement as something to be explained.
- E
The proposed explanation is that natural selection favored some entire species over others. The statement about individuals helps support that explanation, but it doesn't itself supply the account of how sexual reproduction became predominant.
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