Necessary AssumptionDiff: Medium
Logic Breakdown
Passage Summary: This toxic water killed coral that had survived for two hundred years, so this must be the most intense the water has been in at least that long.
Conclusion: The black water phenomenon has not been as intense as last year's event at any point in the previous two centuries.
Reasoning: Last year's event killed coral mounds that were over 200 years old.
Analysis: The argument relies on the 'Missing Link' that the 200-year-old coral would have died if a similar event had occurred earlier. It assumes that the mere existence of the old coral proves that no event of equal or greater intensity happened during its lifespan. To test this, ask if the argument still works if the coral *could* have survived such an event in the past; if it could, the conclusion that this was the 'most intense' event fails.
Conclusion: The black water phenomenon has not been as intense as last year's event at any point in the previous two centuries.
Reasoning: Last year's event killed coral mounds that were over 200 years old.
Analysis: The argument relies on the 'Missing Link' that the 200-year-old coral would have died if a similar event had occurred earlier. It assumes that the mere existence of the old coral proves that no event of equal or greater intensity happened during its lifespan. To test this, ask if the argument still works if the coral *could* have survived such an event in the past; if it could, the conclusion that this was the 'most intense' event fails.
Passage Stimulus
Passage Redacted
Unlock Full Passage11.Which one of the following is an assumption required by the argument?
Correct Answer
D
The argument needs to assume the old corals weren’t unusually fragile just before last year’s event. Negation test: if they were especially fragile, their destruction wouldn’t prove last year’s event was more intense than any in the past 200 years, collapsing the argument.
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