The correct answer is b. Contract law.
The law of agency is a legal framework that governs the relationship between a principal (the person or entity who authorizes an agent to act on their behalf) and an agent (the person authorized to act on behalf of the principal). It establishes the rights, duties, and responsibilities of both parties.
Contract law is closely intertwined with the law of agency because the relationship between a principal and an agent is typically formed through a contract. The contract between the principal and agent outlines the scope of the agent's authority, the obligations of both parties, and the terms and conditions governing their relationship.
While criminal law, constitutional law, and tort law may intersect with agency law in certain circumstances, contract law is most directly associated with the law of agency because it governs the formation, validity, interpretation, and enforcement of the contracts that establish agency relationships.