Under a unilateral contract, what constitutes acceptance?

• A. The offeree's promise to perform in the future.
• B. The offeree's inquiry about the terms.
• C. The start of performance by the offeree.
• D. A written contract signed by both parties.

Answer: (C)

In a unilateral contract, acceptance happens by performing the requested act, not by making a promise. The offer promises payment in exchange for completing a specified task, so the offeree accepts by starting that task. Once the offeree begins performance, the contract is formed and the offeror is obligated to pay once the act is completed (or as specified). Merely promising to perform later isn’t acceptance, and asking questions about terms shows no acceptance yet. A written contract isn’t required for formation in a unilateral contract. For example, if someone offers to pay you to paint a fence, starting to paint constitutes acceptance and forms the contract, even if you haven’t finished yet.