Fact Pattern A Central Construction Company (CCC) begins building a restaurant for Diners Cafe Corporation, but after two months demands an extra $100,000. Diners agrees to pay. Refer to Fact Pattern A. If CCC offers, as a reason for the extra $100,000, that ordinary business expenses have increased, the agreement is a. enforceable as an accord and satisfaction. b. unenforceable due to the preexisting duty rule. c. unenforceable as an illusory promise. d. enforceable because of unforeseen difficulties.