Which of the Following Is True of the Parol Evidence

Multiple Choice

Which of the following is true of the parol evidence rule?

A) If the writing in a contract is clearly incomplete, a party can introduce proof of consistent oral terms that "fill the gaps" in the writing.
B) If the written terms of a contract are unclear, the party can use this exception to alter the concerned part of the contract.
C) Oral testimony that attempts to show that a contract is illegal is not allowed.
D) Proof of contradicting oral agreements that were made after the writing was created is illegal and not enforceable.