Which of the following statements are logically equivalent?

A. No lions are herbivorous animals.

B. No herbivorous animals are lions.

C. All lions are non-herbivorous animals.

D. All non-herbivorous animals are non-lions.

Choose the correct answer from the options given below:

Question

Question

This question was previously asked in

UGC NET Official Paper-I (Held On: 14 Mar, 2023 Shift 2)

Answer 1

Key Points

Statements A, B, and C are logically equivalent because they all express the same relationship between lions and herbivorous animals.
They all indicate that there is no overlap between the sets of lions and herbivorous animals, i.e., there is no lion that is also a herbivorous animal, and there is no herbivorous animal that is also a lion.
Statement D, "All non-herbivorous animals are non-lions." on the other hand, expresses a different relationship between non-herbivorous animals and non-lions.
It indicates that the set of non-herbivorous animals includes all animals that are not herbivorous, and this set also includes all animals that are not lions.

So, while statement D is logically valid, it is not equivalent to statements A, B, or C.