According to the parol evidence rule, what is true about written contracts?

The parol evidence rule is a fundamental principle in contract law that dictates that once a contract is reduced to writing, any prior or contemporaneous oral or written negotiations, agreements, or understandings that contradict or modify the written terms generally cannot be considered. Therefore, the written terms of the contract are treated as the definitive and complete expression of the parties' agreement.

This principle ensures clarity and certainty in contractual relationships by favoring the final written document as the exclusive source of the terms governing the agreement. It prevents the parties from introducing external evidence to change or reinterpret the established terms, thus reinforcing the integrity of the written contract. In situations where disputes arise, the written agreement serves as the primary reference point for enforcement and interpretation, highlighting the essential nature of the written terms in legal proceedings.

The other options do not align with the parol evidence rule's core premise: they imply that extrinsic evidence can alter written contracts or misunderstand what constitutes enforceable agreements. This reinforces the importance of relying solely on the finalized document, which is considered binding and conclusive.