Which of the following is an essential element of a binding contract?

A binding contract must have free consent as one of its essential elements to be enforceable. Free consent means that all parties involved in the contract willingly agree to the terms without any coercion, fraud, undue influence, or misrepresentation. This ensures that each party enters the agreement with a clear understanding and acceptance of what is being promised and expected.

In the context of contract law, free consent promotes fairness and mutual agreement, which are fundamental to establishing a legal obligation that can be upheld in a court of law. Without this element, a contract may be deemed invalid or voidable because it could be argued that one or more parties did not genuinely agree to the terms.

The other options relate to aspects of contract formation but do not represent essential elements of a binding contract. Waiver pertains to the relinquishment of a right, negotiation involves the discussions that lead to an agreement, and revocation refers to the cancellation of an offer or contract. While these can be important in various contractual contexts, they do not fulfill the criteria necessary for the creation of a binding agreement like free consent does.