Gaston tells a group of co-workers that he plans to sell his houseboat. Stephan asks how much he hopes to get for it. Gaston replies, "$30,000." Stephan says, "I accept your offer. I'll purchase your houseboat for $30,000." No Contract exists because

A. made a counteroffer

B. they don't seriously intend to enter a contract

C. the offer isn't properly communicated

D. the terms of the offer aren't reasonably certain