What Would a Negotiator Most Likely Caution Against with Respect

Multiple Choice

What would a negotiator most likely caution against with respect to the notion of building flexibility into contractual agreements?

A) the risk of having no contract at all if the resulting document is too unfixed
B) the risk that the parties will be allowed to terminate the contract altogether
C) the risk of having the parol evidence applied regarding evidence of intent
D) the risk that voluntarily altering the contract will make it unenforceable