Correct option is A
Option (a) is the correct antonym of the given word.
Under (नीचे) refers to a position or location beneath or below something else.
Example- Vast stores of gas under the North Sea.
Synonyms: Beneath, below, underneath.
Antonyms: Above, over, on top of.
Meanings of all options:
· Over: Above or higher than something.
· Sink: To descend or submerge into a liquid or lower position.
· Behind: In a position at the rear or back of something.
· Beneath: Below or underneath something else.