Statements: All A are B. No B are C. Conclusion: Some C are A. This conclusion is
- A. valid
- B. invalid
- C. always true
- D. possibly true
Explanation
A is inside B, and B is entirely separate from C, so no A can be C at all, which makes the proposed conclusion the exact opposite of what follows. Using letters rather than familiar words removes the temptation to reason from world knowledge. The valid conclusion here is that no A is C.
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