If the statement 'No birds are animals' is given as false, which of the following statements can be inferred to be true?

1.Some animals are not birds.

2.Some birds are not animals.

3.Some animals are birds.

4.Some birds are animals.

A1 & 2 only

B3 & 4 only ✓ Correct

C2 only

D1, 2, 3 & 4

Correct answer: (B) 3 & 4 only

Explanation

Given 'No birds are animals' is false, its contradictory 'Some birds are animals' must be true.

That true particular affirmative is Statement 4.

Since the particular affirmative converts simply, 'Some animals are birds' is also true, which is Statement 3.

Statements 1 and 2 are particular negatives, and the falsity of the universal negative leaves them undetermined.

So only the two particular affirmatives can be inferred true.

Hence the certain truths are the third and the fourth.

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