Every(ক) man or woman should(খ) vote for(গ) the candidate of their(ঘ) choice.
Every
should vote
for
their
Explanation:
Correct Answer is: their
Every + singular noun subject হলে তার পরবর্তী pronoun টিও singular হবে। Their হলে plural, তাই এখানে singular pronoun `his/her` হবে।