Why is the answer "will have worked" but not "will have been working"?

Which statement best represents a claim? a.people who do not exercise their right to vote are truly wasting a precious democratic privilege. b.the benefits of mandatory voting in the united states far outweigh the potential drawbacks. c.some countries require people who do not vote in certain elections to pay a moderate fine. d. i would never want to live in a country where it was mandatory to vote in political elections.