Which type of contract allows a buyer the right to purchase but not the obligation to do so?

The correct choice is the option contract, which is a specific type of contract that grants the buyer the right, but not the obligation, to purchase a property at a predetermined price within a specified timeframe. This type of agreement provides the buyer with a unique advantage, as they can choose to exercise the option if market conditions are favorable or if they decide to proceed with the purchase. If the buyer opts not to purchase, they are not legally bound to do so, allowing for flexibility in their decision-making.

In contrast, a standard purchase agreement generally involves a commitment to buy and sell, meaning both parties have obligations that must be fulfilled. A lease agreement creates an obligation for the lessee to pay rent, which does not include a purchase option, and a contingency contract involves conditions that must be met for the transaction to be finalized. Therefore, the defining characteristic of an option contract is its provision of choice to the buyer without encumbering them with a mandatory purchase, underscoring the rationale for its selection as the correct answer.