Which of the following best defines dual agency?

The correct answer identifies dual agency as a situation where one broker represents both the buyer and the seller in a real estate transaction. This definition captures the essence of dual agency, which is characterized by the broker's involvement in facilitating the transaction for both parties, maintaining a balance in their duties and responsibilities.

In dual agency, the broker must navigate the potential conflicts of interest that arise because they have fiduciary duties to both the buyer and the seller. This arrangement requires transparency and informed consent from both parties, ensuring that they understand the broker's role and any limitations on the broker's ability to advocate for one party over the other.

The other options describe different scenarios that do not align with the definition of dual agency. Representing opposing parties typically involves separate brokers, which would be considered a form of traditional agency rather than dual agency. The idea of representing a buyer without a seller does not encompass dual agency, as it implies that only one party is involved. Lastly, a method of advertising a property is unrelated to agency relationships and does not pertain to the definition of dual agency. Thus, the chosen answer accurately encapsulates the concept within the context of real estate practices.