Correct option is A
The correct antonym of the given word is
(a) kind.
Given word (Callous): It means emotionally insensitive; showing no sympathy for others’ feelings or suffering. (Hindi meaning: निर्दयी, संवेदनहीन)
Example: His callous remarks hurt everyone.
Correct answer word (Kind): It means caring, helpful, and sympathetic towards others. (Hindi meaning: दयालु, कृपालु)
Example: She is kind to everyone.
Synonyms (callous): heartless, insensitive, unfeeling, cruel.
Antonyms: kind, compassionate, sympathetic, considerate.
Meanings of all the other given options:
• (b) Cruel: causing pain intentionally; harsh (क्रूर)
• (c) Generous: giving freely; large-hearted (उदार)
• (d) Optimistic: hopeful and positive (आशावादी)