For a contract to be considered valid, which of the following must be true?

For a contract to be considered valid, it is essential that it is based on an offer and acceptance. This fundamental principle establishes the agreement between the parties involved, indicating that one party has made a proposal (the offer) and the other party has agreed to the terms (the acceptance). This mutual consent is a critical element of contract law, as it signifies that both parties have a clear understanding of their rights and obligations.

In addition, while other aspects may bolster a contract's enforceability or validity, such as signatures, notarization, or specific subject matter like real estate, they are not universally required for all contracts to be considered valid. For instance, a contract can still be valid without a witness or notarization as long as there is clear offer and acceptance. Therefore, understanding the principle of offer and acceptance is crucial for recognizing the validity of contracts in various contexts, particularly in real estate transactions.