What type of contract requires both parties to fulfill certain obligations to be enforceable?

The correct answer is that a conditional contract requires both parties to fulfill certain obligations to be enforceable. In a conditional contract, the performance of one or both parties is contingent upon the occurrence of a specified event or condition. This means that neither party is bound to perform their obligations until the conditions outlined in the contract are satisfied. This mutual dependency creates the enforceability of the contract, as both parties must meet their obligations for the agreement to take effect.

The other types of contracts differ in their requirements. A unilateral contract, for instance, involves a promise made by one party in exchange for an action by another party, and is enforceable when that action is performed. A mutual contract typically refers to any agreement where there is a mutual assent between the parties, but it does not specifically denote a requirement for conditions to be met for enforceability. An aleatory contract involves an element of chance, where the performance or benefits are contingent on uncertain events, making it less about fulfilling obligations than about the occurrence of those uncertain events. Therefore, the defining characteristic of a conditional contract is its requirement for specific conditions to be met, which is why it is the correct choice in this context.