Reference - Wrong Deck

Reference - Wrong Deck. Penny hires Jackson to paint her back deck on her house. She agrees to pay him $200 for the job, and he accepts, sight unseen. They enter into the agreement on Tuesday, and he is to paint the deck on Saturday. When Jackson arrives, neither Penny nor her neighbor is at home. He mistakenly paints the neighbor's deck. Penny calls him the next day and asks him why he did not paint her deck. He informs her that he did paint the deck. It is then discovered that he mistakenly painted the neighbor's deck. Penny tells him not to worry because the neighbor will be required to pay him. Jackson says that if the neighbor does not pay, then he expects all of his funds from Penny. Which of the following is true regarding Jackson's assertion that Penny must pay him?

A) He is correct because an express contract existed.
B) He is correct because an implied contract existed.
C) He is correct because an implied-in-law contract existed.
D) He is correct because a valid contract existed.
E) He is incorrect unless he can somehow establish that Penny gave him poor directions or was otherwise at fault in informing him which deck to paint.