Synonyms are words which have the same or nearly the same meaning in the same language.
Antonyms are words which have opposite meaning in comparison to the other.
Option A)Claim is correct as the word claim means state or assert that something is the case, typically without providing evidence or proof and the word abandon means cease to support or look after (someone); desert. Abandon and claim are opposite in meaning.
The other options are not correct as forfeit means lose or be deprived of (property or a right or privilege) as a penalty for wrongdoing, quit means leave (a place), usually permanently., and forsake means abandon or leave.