alleryStart learning →If it is false that no A are B, which cannot be validly inferred?
ANot all A are non-B
BAll A are certainly B
CSome B are also A
DAt least one A is B
Answer & Solution
Correct answer: B. All A are certainly B
Denying 'no A are B' gives only 'some A are B'; claiming 'all A are B' is the illicit contrary.
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