Question

3 tries left
for a contract to be considered legally enforceable, parties who
must make the contract.
are unrelated to each other
are familiar with each other
have permission from their boss
are legally able to contract

Explanation:

A legally enforceable contract requires that the parties involved have the legal capacity to enter into a contract. Relationship (unrelated or familiar) or permission from a boss is not a fundamental legal requirement for contract enforceability. Legal ability to contract (such as being of legal age, having mental capacity etc.) is crucial.

Answer:

are legally able to contract