Necessary AssumptionDiff: Easy
Logic Breakdown
Passage Summary: When these birds are losing their feathers and can't fly well, they sing a special song that keeps other yellow warblers away from their food supply.
Conclusion: Molting yellow warblers do not have to compete for food within their limited flying range.
Reasoning: During molting, warblers sing a specific song that prevents other yellow warblers from entering their core territory.
Analysis: The 'gap' in this argument is the scope of the competition. The premises tell us that the song keeps other 'yellow warblers' away, but the conclusion claims there is 'no competition' for food at all. This assumes that no other species or factors compete for that same food. To find the necessary assumption, look for an answer that eliminates other potential competitors, such as different bird species or insects, that wouldn't be deterred by a yellow warbler's song.
Conclusion: Molting yellow warblers do not have to compete for food within their limited flying range.
Reasoning: During molting, warblers sing a specific song that prevents other yellow warblers from entering their core territory.
Analysis: The 'gap' in this argument is the scope of the competition. The premises tell us that the song keeps other 'yellow warblers' away, but the conclusion claims there is 'no competition' for food at all. This assumes that no other species or factors compete for that same food. To find the necessary assumption, look for an answer that eliminates other potential competitors, such as different bird species or insects, that wouldn't be deterred by a yellow warbler's song.
Passage Stimulus
Passage Redacted
Unlock Full Passage4.The argument makes which one of the following assumptions?
Correct Answer
C
Correct. The argument needs it to be true that no other bird species compete for the same food. Negation test: If other birds do compete with yellow warblers for food, then even if yellow warblers avoid the core area, the molting bird could still face competition there—destroying the conclusion of “no competition.”
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