Final answer:
An aleatory contract is where parties exchange unequal amounts of money and obligations depend on uncertain events, unlike conditional, executory, or unilateral contracts.
Step-by-step explanation:
When parties to a contract exchange unequal amounts of money, the contract is termed an aleatory contract. An aleatory contract is a type of agreement where the performance and obligations of the parties depend on some event which is uncertain to occur.
his is in contrast to most contracts where there are equal exchanges or where the performance is certain to occur. Examples of aleatory contracts include insurance policies and gambling bets. Other options like conditional, executory, and unilateral do not describe contracts based on unequal monetary exchange.