The correct option is A repels
The word 'attracts' refers to causing someone to have a liking or interest in someone.
Option A, instigates refers to bringing about or initiating an action or event.
Option B, annoys refers to making someone a little angry.
Option C, repels refers to being repulsive or distasteful towards something.
Option D, revolts refers to an attempt to end the authority of a person or body by rebelling.
Thus, according to the meaning, the word 'repels' is the opposite of the word 'attracts'.