PrepTest 156, Section 2, Question 24
Researcher: Several chemical compounds found in soybeans are(64 more words not shown)
Each of the following, if(27 more words not shown)
- AThe soybean derivatives(19 more words not shown)
- BWhile phytosterols, which(31 more words not shown)
- CA study of(20 more words not shown)
- DConsumption of soybean(31 more words not shown)
- EPreliminary studies have(13 more words not shown)
Reading the argument
How much of these compounds would a person need? Even if a soybean contains something helpful, an ordinary serving might not deliver enough of it. And evidence about animals doesn't automatically settle what happens in humans.
The researcher gives two possible routes to cancer prevention. Isoflavones inhibit estrogen production in the animals studied, and estrogen promotes certain cancers. Phytosterols may reduce cholesterol absorption and thereby have anticancer effects. I'd want to check whether those paths work in humans and whether the effects are large enough to matter. We could also ask whether some other effect offsets the proposed benefit.
What we’re looking for
This is a weaken-except question. Four answers should reduce the support for effective human cancer prevention; one won't. Keep the claim precise: the compounds' effectiveness is at issue. Keep our dosage question in mind without turning this into a broader claim that any amount of ordinary soybeans must help.
Working the answers
- ACorrect
A specially processed compound could be effective even if consumers can't yet obtain it widely. Manufacturing and availability don't establish whether it prevents cancer. The researcher doesn't claim that every consumer can currently get the preparation, so this limitation leaves the claimed effectiveness untouched. That's why A is the exception.
- B
This cuts the proposed cholesterol route at the next step. Even if phytosterols decrease absorption, the decrease isn't large enough to reduce susceptibility to cancer. A real intermediate effect doesn't establish the ultimate benefit the researcher wants to claim.
- C
People with high cholesterol don't show a significant reduction after switching to a soybean-rich diet. That weakens support for the hoped-for cholesterol effect in humans. It isn't decisive: a concentrated preparation might work even if ordinary dietary amounts don't. But the question only requires reduced support, and this disappointing human result supplies some.
- D
Here too, a human population eating substantial soy doesn't show lower-than-normal cholesterol. That makes the move from possible animal benefits to human benefits less persuasive. It doesn't prove the compounds could never help at a different dose or in a different preparation, but it gives us a reason to question the proposed pathway in humans.
- E
The isoflavone evidence in the passage comes from animals. Preliminary human studies don't show a significant estrogen effect, so they challenge carrying that result over to humans. 'Preliminary' limits how much we should conclude, but it doesn't make the evidence irrelevant. Even a modest challenge to effectiveness is different from A's information about availability.
More Weaken questions
Learn the LSAT our way
Our platform drills Weaken questions at your level and adjusts as you improve.