Which of the following statements is logically equivalent to the statement No frogs are mammals?

ANo mammals are frogs ✓ Correct

BAll non-mammals are non-frogs

CSome non-mammals are not non-frogs

DSome mammals are non-frogs

Correct answer: (A) No mammals are frogs

Explanation

No mammals are frogs is logically equivalent to the given statement.

No frogs are mammals is a universal negative, type E.

An E proposition converts validly by exchanging subject and predicate.

That exchange yields No mammals are frogs with identical truth conditions.

Conversion of E preserves logical equivalence.

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