Which of the following is a key characteristic of a contract?

A key characteristic of a contract is that it must be enforceable by law. This means that for a contract to be valid, it must establish the parties' obligations in a way that the law recognizes and can enforce. If a contract lacks enforceability, it may not hold any legal weight, making it essentially void or voidable.

This enforceability depends on several factors, including the presence of mutual assent (offer and acceptance), consideration (something of value exchanged), legal capacity of the parties, and a lawful purpose. When a contract meets these requirements, any party can seek legal remedies in the event of a breach, thus highlighting its enforceability.

In contrast, while contracts can be verbal or written, they are not required to adhere to a specific format. The idea that a contract is always written is overly restrictive, as many contracts can be legally binding even if they are spoken. The misconception that a contract doesn't require consideration is also inaccurate, as consideration is a fundamental element; without it, a contract is often unenforceable.