Necessary AssumptionDiff: Easy
Logic Breakdown
Passage Summary: Box jellyfish have eyes that could be great but are actually blurry; a biologist thinks this proves animals only evolve the vision they actually need.
Conclusion: Eye design in animals is determined by their specific survival needs rather than an abstract standard of what makes a 'good' eye.
Reasoning: Box jellyfish have the physical hardware for sharp vision, but their retinas are positioned such that they only see blurry images.
Analysis: The biologist is making a leap from the observation of 'blurry vision' to the conclusion that 'sharp vision isn't needed.' For this to hold up, the argument must assume that the blurry vision isn't a disadvantage or a failure of adaptation. If the jellyfish actually needed sharp vision to survive better, the argument that eyes only adapt to 'needs' would fall apart. Look for an answer that confirms the jellyfish does not require sharp images for its survival.
Conclusion: Eye design in animals is determined by their specific survival needs rather than an abstract standard of what makes a 'good' eye.
Reasoning: Box jellyfish have the physical hardware for sharp vision, but their retinas are positioned such that they only see blurry images.
Analysis: The biologist is making a leap from the observation of 'blurry vision' to the conclusion that 'sharp vision isn't needed.' For this to hold up, the argument must assume that the blurry vision isn't a disadvantage or a failure of adaptation. If the jellyfish actually needed sharp vision to survive better, the argument that eyes only adapt to 'needs' would fall apart. Look for an answer that confirms the jellyfish does not require sharp images for its survival.
Passage Stimulus
Passage Redacted
Unlock Full Passage8.The argument requires assuming which one of the following?
Correct Answer
B
Question type: Necessary Assumption. Reasoning gap: The argument assumes that box jellyfish do not need fine detail and that being able to detect prominent features is sufficient for their needs. Without that, the example would not show adaptation to needs; it could instead show a suboptimal or maladaptive eye. Negation test: If box jellyfish do need fine detail, the blurry image would not meet their needs, and the example would fail to support the conclusion.
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