Necessary AssumptionDiff: Hard
Logic Breakdown
Passage Summary: A deadly brain condition is caused by the same thin air as common mountain sickness and looks just like it, making it extra dangerous for climbers.
Conclusion: Cerebral edema is particularly hazardous when it occurs at high altitudes.
Reasoning: Both mountain sickness and cerebral edema are caused by low oxygen and share similar symptoms, but cerebral edema is much more lethal.
Analysis: The argument relies on a missing link between the similarity of symptoms and the increase in danger. It assumes that because the two conditions look alike, people will mistake the deadly one for the harmless one, leading to a lack of proper treatment. To identify the necessary assumption, ask yourself what must be true for the 'danger' to be 'especially' high—it likely involves the inability of climbers or medics to distinguish between the two. If they could tell them apart easily, the similarity in symptoms wouldn't actually make the condition more dangerous.
Conclusion: Cerebral edema is particularly hazardous when it occurs at high altitudes.
Reasoning: Both mountain sickness and cerebral edema are caused by low oxygen and share similar symptoms, but cerebral edema is much more lethal.
Analysis: The argument relies on a missing link between the similarity of symptoms and the increase in danger. It assumes that because the two conditions look alike, people will mistake the deadly one for the harmless one, leading to a lack of proper treatment. To identify the necessary assumption, ask yourself what must be true for the 'danger' to be 'especially' high—it likely involves the inability of climbers or medics to distinguish between the two. If they could tell them apart easily, the similarity in symptoms wouldn't actually make the condition more dangerous.
Passage Stimulus
Passage Redacted
Unlock Full Passage15.Which one of the following is an assumption on which the argument depends?
Correct Answer
A
A states the needed bridge: the treatments differ. Negation test: if the treatments did not differ (i.e., were the same), then mistaking cerebral edema for ordinary mountain sickness would not jeopardize the patient—there would be no special danger from symptom similarity. That collapse shows A is necessary.
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