WeakenDiff: Medium
Logic Breakdown
Passage Summary: Farmers switched to a new bug spray for three years and saw fewer pears ruined by bugs than in the previous three years, so an official thinks the new spray works better.
Conclusion: The new pesticide is more effective than the old one at reducing fruit loss to insects in the short term.
Reasoning: After switching to the new pesticide for three years, the percentage of pears lost to insects was lower than it had been during the three years prior.
Analysis: This is a classic correlation-to-causation flaw where the official assumes the pesticide is the sole reason for the improvement. To weaken this, we need factors other than the pesticide that could explain the decrease in insect damage, such as weather changes or natural insect cycles. Since this is a 'Weaken EXCEPT' question, four choices will provide these alternative explanations, while the correct one will either be irrelevant or actually support the conclusion. Look for an answer that doesn't offer a reason why the drop in losses might have happened regardless of the pesticide switch.
Conclusion: The new pesticide is more effective than the old one at reducing fruit loss to insects in the short term.
Reasoning: After switching to the new pesticide for three years, the percentage of pears lost to insects was lower than it had been during the three years prior.
Analysis: This is a classic correlation-to-causation flaw where the official assumes the pesticide is the sole reason for the improvement. To weaken this, we need factors other than the pesticide that could explain the decrease in insect damage, such as weather changes or natural insect cycles. Since this is a 'Weaken EXCEPT' question, four choices will provide these alternative explanations, while the correct one will either be irrelevant or actually support the conclusion. Look for an answer that doesn't offer a reason why the drop in losses might have happened regardless of the pesticide switch.
Passage Stimulus
Passage Redacted
Unlock Full Passage8.Each of the following, if true, weakens the official's argument EXCEPT:
Correct Answer
A
A doesn’t weaken the argument about proportion lost. Fewer mature trees reduce potential fruit, but that doesn’t explain why the proportion of pears lost to insects fell; if anything, fewer pears could make a given insect presence harm a larger share, not a smaller one. So this is not a plausible alternative cause of the reduced proportion.
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