A notorious spendthrift, who was usually broke for that reason, received the following letter from his uncle, a wealthy and prudent man: "I understand you're in financial difficulties again. I promise to give you $5,000 on your birthday next month, but you'd better use it wisely or you'll never get another dime from me." The spendthrift thereupon signed a contract with a car dealer to purchase a $40,000 automobile and to make a $5,000 down payment on the day after his birthday. If the spendthrift sues the uncle for $5,000 after the latter learned of the car-purchase contract and then repudiated his promise, which of the following is the uncle's best defense? A. A promise to make a gift in the future is not enforceable.
B. Reliance by the promisee on a promise to make a future gift does not make the promise enforceable unless the value of the promised gift is substantially equivalent to the promisee's loss by reliance.
C. Reliance by the promisee on a promise to make a future gift does not make the promise enforceable unless that reliance also results in an economic benefit to the promisor.
D. Reliance by the promisee on a promise to make a future gift does not make the promise enforceable unless injustice can be avoided only by such enforcement.