Which of the following statements are logically equivalent? Choose the correct answer from the options given below.

1.Some drinks are not liquids.

2.Some drinks are liquids.

3.Some non-liquids are not non-drinks.

4.Some drinks are non-liquids.

A1, 2 only

B2, 3, 4 only

C2, 3 only

D1, 3, 4 only ✓ Correct

Correct answer: (D) 1, 3, 4 only

Explanation

Three propositions are equivalent, all expressing "some drinks are not liquids".

Statement 1 is the original particular negative O, "Some drinks are not liquids".

Statement 4, "Some drinks are non-liquids", is the obverse of that O and keeps its meaning.

Statement 3, "Some non-liquids are not non-drinks", reduces by obversion and conversion to the same content.

Statement 2, "Some drinks are liquids", is an independent I proposition and does not follow.

Obversion and conversion holding truth make Statements 1, 3 and 4 logically equivalent.

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