Which of the following is true regarding oral contracts?

Oral contracts can indeed be legally binding under certain circumstances, making the statement that they can be legally binding true. The enforceability of an oral contract typically depends on the subject matter of the agreement and the jurisdiction in which it is made. In many cases, oral contracts are valid and enforceable unless specified otherwise by statute, such as in the Statute of Frauds, which requires certain contracts to be in writing to be enforceable (like contracts for the sale of real estate).

For instance, oral agreements for services or the sale of goods below a certain monetary threshold often do not require a written document to be valid. However, while they are enforceable, they are generally harder to prove in a dispute due to the lack of written evidence, which is why formalizing agreements in writing is often encouraged.

The other options present statements that limit the validity or enforceability of oral contracts unnecessarily. Requiring written documentation or witnesses can apply to specific types of agreements as outlined by law but is not a blanket requirement for all oral contracts.