Which of the following statements are so related that they cannot both be true, although they both may be false?

1.All trees have roots

2.No trees have roots

3.Some trees have roots

4.Some trees do not have roots

A3 & 4 only

B1 & 2 only ✓ Correct

C2 & 4 only

D1 & 3 only

Correct answer: (B) 1 & 2 only

Explanation

Statement 1 and Statement 2 cannot both be true yet may both be false.

That relation is contrariety between two universals.

Statement 1 is the universal affirmative A, All trees have roots.

Statement 2 is the universal negative E, No trees have roots.

Opposed universals A and E are contraries on the square of opposition.

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