If the statement Some animals are birds is given as true, which of the following statements can be immediately inferred to be false?

ANo animals are birds ✓ Correct

BAll animals are birds

CSome animals are not birds

DAll animals cannot fly

Correct answer: (A) No animals are birds

Explanation

The proposition No animals are birds must be false.

The given truth is the I proposition Some animals are birds.

Its contradictory is the E proposition No animals are birds.

Contradictories always take opposite truth values, so if I is true then E is false.

Hence No animals are birds is immediately inferred to be false.

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