Jack Is Speaking to Michael and Michael a Happens to Mention

Jack is speaking to Michael and Michael a happens to mention that he will be painting is home soon. Jack, who is in some financial difficulty decides to paint Michael's home in the hope that Michael will pay for the service. One weekend, when Michael is away, Jack paints the whole house. He believes that he is entitled to approximately $1,500. When Michael returns, Jack approaches him and asks for $1,500. Which of the following is true?

A) Jack's conduct is an invitation to do business that has not been accepted by Michael and so Michael is not obliged to pay him.
B) Jack, by painting the home, makes an offer that Michael is free to accept or reject.
C) When Michael mentions the need to paint his home to Jack, he indirectly makes an offer that Jack accepts by painting the home.
D) Michael has benefited from the painted home and so he is obliged to pay for it.
E) Michael is not obliged to pay for the work done because he was never made any offer.