Which of the following propositions are so related that one is the denial or negation of the other?

1.All electric vehicles are environment-friendly transportation media

2.Some electric vehicles are environment-friendly transportation media

3.No electric trains are environment-friendly transportation media

4.Some electric vehicles are not environment-friendly transportation media

A1 & 3 only

B1 & 4 only ✓ Correct

C2 & 4 only

D3 & 4 only

Correct answer: (B) 1 & 4 only

Explanation

The pair that are exact denials of each other are All electric vehicles and Some electric vehicles are not.

Contradictories are the A and O forms sharing the same subject and predicate.

Statement 1 is A and Statement 4 is O over electric vehicles and environment-friendly media.

Statement 3 concerns electric trains, a different subject, so it forms no contradictory pair here.

Contradictories always differ in both quantity and quality and cannot share a truth value.

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