LSAT 156 | Section 2 | Logical Reasoning: Q24

LR Question 24 Explanation

QUESTION TEXT: Researcher: Several chemical compounds found in soybeans …

QUESTION TYPE: Weaken – EXCEPT

CONCLUSION: Several compounds in soybeans are effective for preventing cancer in humans.

REASONING: The researcher points to two possible mechanisms, both of which could help prevent cancer:

1. Isoflavones may reduce estrogen
2. Phytosterols may reduce cholesterol

ANALYSIS: This is an EXCEPT question, so four answers will weaken the efficacy of soybeans. One should leave it mostly intact.

The support in the stimulus is all about whether these soybean compounds actually have anticancer effects in humans. So answers that show the compounds do not have those effects in humans, or that the supposed mechanism does not really reduce cancer risk, will weaken the argument. Those are answers we don’t want.

___________

1. CORRECT. This doesn’t really weaken. Even if the tested derivatives are not widely available, that does not show the compounds are ineffective. It just raises a practical issue about access.
2. This weakens. If phytosterols lower cholesterol absorption but not enough to reduce cancer risk, then that proposed anticancer mechanism loses force.
3. This also weakens. If a soybean-rich diet doesn’t significantly reduce cholesterol in people, that undermines the phytosterol argument.
4. Also weakens. If people whose main protein source is soy don’t have lower cholesterol than normal, that gives less reason to think soy reduces cancer through cholesterol reduction.
5. Also weakens. If isoflavones do not significantly affect estrogen levels in humans, that removes one of the potential mechanisms.