Which of the following statements is the contrapositive of All whales are mammals?

ASome whales are mammals

BAll non-mammals are non-whales ✓ Correct

CSome mammals are whales

DAll mammals are whales

Correct answer: (B) All non-mammals are non-whales

Explanation

The contrapositive is All non-mammals are non-whales.

The original is the A proposition All whales are mammals, with whales as subject and mammals as predicate.

Forming the contrapositive replaces each term with its complement and interchanges them.

Subject and predicate become non-mammals and non-whales respectively.

The A form and its contrapositive are logically equivalent, giving All non-mammals are non-whales.

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