Dunne and Cook signed a contract requiring Cook to rebind 500 of Dunne’s books at $0.80 per book. Later, Dunne requested, in good faith, that the price be reduced to

$.70 per book. Cook agreed orally to reduce the price to

$.70. Under the circumstances, the oral agreement is

a. Enforceable, but proof of it is inadmissible into evidence.

b. Enforceable, and proof of it is admissible into evidence.

c. Unenforceable, because Dunne failed to give consideration, but proof of it is otherwise admissible into evidence.

d. Unenforceable, due to the statute of frauds, and proof of it is inadmissible into evidence.