When Maria Comes Home from Work, She Finds That Her

When Maria comes home from work, she finds that her yard has been mowed and trimmed. An hour later a man comes to her door to collect payment for the yard work. Maria refuses to pay him because she has never seen him before and had not hired him to do the work. Which of the following is accurate?

A) This is an implied, unilateral contract, so she must pay.
B) Maria has received unjust enrichment, so a quasi-contract is formed and she must pay.
C) The court would make Maria pay the reasonable cost of the work to be fair to both parties.
D) Maria would not have to pay anything.