What characterizes a unilateral contract?

A unilateral contract is defined by its structure, where one party makes a promise that is contingent upon the other party's performance of a specific act. In this type of contract, one party’s commitment is not contingent upon any promise or performance from the other party, but rather the contract is fulfilled when the other party completes the action requested. This means that the party offering the contract is bound to fulfill their promise only if the other party performs the act in question.

For instance, a classic example of a unilateral contract is a reward offer for finding a lost pet. The person offering the reward promises to pay it upon the successful return of the pet, and there is no need for the person looking for the pet to make any promises in return; they simply need to fulfill the action of returning the lost pet.

The other options describe different types of contractual arrangements or do not adequately capture the essence of a unilateral contract. The first choice describes a bilateral contract, where both parties exchange promises. The second option suggests a lack of enforceability, which does not accurately characterize unilateral contracts, as they can be legally binding under the right conditions. The last option implies multiple stakeholders are involved, which can be a feature of different contract types, but it does not define a