Reference - Garage Sale

Reference - Garage sale. Richard, who is cleaning out his garage, offers to sell Dawn a used computer for $200. Dawn replies that "I'll think about it and buy it if I decide to do so." Richard also calls Denise and offers to give Denise a used business law book. She is excited to receive the book and tells him that she will pick it up the next day. Richard also agrees to sell a communications book for $50 to Jill who promises to pick it up the next day. Meanwhile, Sam comes to visit, offers Richard $20 for the business law book and Richard sells it to him. Sam also offers Richard $50 for the used computer. Richard sells it to Sam because he does not expect to hear from Dawn. Sam sees the communications book and offers Richard $60 for it. Richard decides to forget about Jill and proceeds to sell the book to Sam for $60. Denise is very angry because Richard did not save the book for her and claims that he breached a contract because she had accepted his offer. Jill is also angry because Richard sold the communications book and informs him that he breached the contract he had with her. Exactly 31 days later, Dawn tells Richard that she would like the computer. She tells him that her response constituted consideration in that it bound him to an option contract and that he should have awaited her final decision. Richard tells Sam that he needs to return everything for a full refund. Sam refuses. Which of the following is true regarding the dispute between Richard and Sam regarding whether Sam must return anything?

A) Sam must return the computer only.
B) Sam must return the business law book only.
C) Sam must return the communications book only.
D) Sam must return the computer, the business law book, and the communications book.
E) Sam does not legally have to return anything.