According to the law of agency, sellers who contract with real estate brokers to market their property and represent them in the sale of their property are the:

Agents are individuals or entities that act on behalf of another party, known as the principal. In this scenario, the real estate brokers serve as agents for the sellers, facilitating the sale of the property. Therefore, while agents play a crucial role in the transaction, they do not represent the sellers as principals.

Grantors typically refer to individuals who transfer property rights to another person, commonly used in the context of deeds or trusts. In this case, the sellers are not transferring property rights in the same sense; rather, they are hiring brokers to represent them in a sale, making "grantors" an inaccurate choice.

While sellers may be considered customers of the real estate services, this term lacks the legal specificity needed in the context of agency law. The term "customer" does not convey the authority the sellers have in contracting with brokers, thus failing to accurately reflect their role in the agency relationship.