Which of the following is NOT a characteristic of a unilateral contract?

A unilateral contract is a specific type of contract where only one party, known as the offeror, makes a promise or offer, and the other party, or offeree, accepts the offer solely by performing a specific action.

The defining feature of a unilateral contract is that it does not necessitate a reciprocal exchange of promises between the parties involved. Instead, the contract is fulfilled when the offeree performs the act stipulated in the offer. This highlights why the characteristic of involving an exchange of promises is not applicable. In contrast to bilateral contracts, where both parties agree to fulfill their respective obligations, unilateral contracts are only binding on the party that made the promise until the specified action is completed by the offeree.

The other characteristics mentioned accurately describe unilateral contracts. They are binding for only one party (the promise-maker), they involve an offeror and offeree, and they can indeed be enforced in a court of law, which reinforces the legally binding nature of unilateral contracts once the conditions have been met by the offeree.