Which type of contract is deemed 'unilateral' in nature?

A unilateral contract is characterized by its binding nature on only one party while the other party is not required to fulfill any obligations. In such contracts, one party makes a promise in exchange for a specific action or performance from the other. This means that the offeror is the only party who has an obligation under the contract until the other party completes the action that the offeror has promised to reward.

In contrast, a contract with mutual obligations requires both parties to fulfill their respective commitments, which would classify it as a bilateral contract. A contract that mandates performance from both parties also indicates a mutual obligation, reinforcing the bilateral nature. Lastly, while being negotiable is a feature of contracts in general, it does not specifically define the nature of obligations between the parties involved. Thus, option B accurately captures the essence of a unilateral contract, illustrating that it is only binding on one party until the conditions of the contract are fulfilled.