Which one of these duties serves as the overarching duty for agents?

The duty of loyalty serves as the overarching duty for agents because it fundamentally ensures that the agent acts in the best interests of the principal, placing the principal's interests above their own. This duty encompasses avoiding conflicts of interest, making full disclosures to the principal, and not engaging in self-dealing or benefiting personally at the expense of the principal. By prioritizing the principal's interests, the agent maintains a trust-based relationship that is critical to the agency's success.

While the duty of obedience, the duty to compensate, and the duty to cooperate are also important duties in the agent-principal relationship, they do not encapsulate the essence of the fiduciary relationship in the same way. The duty of obedience requires the agent to follow the principal's lawful instructions, the duty to compensate relates to payment for services rendered, and the duty to cooperate involves facilitating the principal's objectives. However, these duties are all secondary to the overarching duty of loyalty, which is essential in maintaining the trust and integrity at the core of the agency relationship.