Which type of contract may be considered valid but is unenforceable in court?

An unenforceable contract is considered valid in the sense that it meets the basic requirements of a contract, such as offer, acceptance, and consideration; however, it cannot be enforced in a court of law due to certain legal defenses or statute limitations. For instance, this can occur when the contract lacks a necessary element that makes it enforceable, such as proper signing requirements or when it pertains to a subject matter that is not legally binding under the law.

In practice, while the agreement may be valid between the parties and both may have fulfilled their obligations, if one party were to seek legal enforcement of the contract, the court would refuse to enforce it. An example of this could be a contract for the sale of real estate that is not in writing, as required by the Statute of Frauds.

The other options highlight different aspects of contracts: a void contract is not valid from the outset and has no legal effect; a rescinded contract has been canceled by mutual agreement before performance; and a breach of contract occurs when one party fails to fulfill their obligations under the agreed-upon terms. These concepts illustrate different legal standings of agreements but do not pertain to the scenario where a contract remains valid yet unenforceable as specified in the question.