Sufficient AssumptionDiff: Medium
Logic Breakdown
Passage Summary: Some students live off campus, and every music major is in the choir. The professor thinks this means no off-campus student is a music major.
Conclusion: No student who lives off campus is a music major.
Reasoning: All music majors are members of the university choir, and some students at the university live off campus.
Analysis: The professor is making a leap from 'all music majors are in the choir' to a total exclusion of off-campus students from the music department. For this to be a valid deduction, there must be a rule that separates choir members from off-campus residents entirely. To guarantee this conclusion, we need an assumption that states no member of the choir lives off campus.
Conclusion: No student who lives off campus is a music major.
Reasoning: All music majors are members of the university choir, and some students at the university live off campus.
Analysis: The professor is making a leap from 'all music majors are in the choir' to a total exclusion of off-campus students from the music department. For this to be a valid deduction, there must be a rule that separates choir members from off-campus residents entirely. To guarantee this conclusion, we need an assumption that states no member of the choir lives off campus.
Passage Stimulus
Passage Redacted
Unlock Full Passage8.The professor's conclusion is properly drawn if which one of the following is assumed?
Correct Answer
A
Assuming none of the off-campus students is a choir member (O → ~~C~~), and given all music majors are in the choir (M → C, so ~~C~~ → ~~M~~), we get O → ~~M~~. That exactly yields the professor’s conclusion.
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