How must a real estate brokerage agency's trade name be displayed in advertising?

The correct answer emphasizes the importance of transparency and identification in real estate advertising. A real estate brokerage agency's trade name must be prominently displayed to ensure that consumers can easily identify the entity responsible for the advertisement. This regulation serves to protect consumers by making it clear which agency is involved in the transaction, thus preventing confusion and misrepresentation.

When the trade name is shown prominently, it allows potential clients to know who they are dealing with, fostering trust and awareness about the agency's brand. This requirement aligns with regulatory standards aimed at maintaining professionalism within the real estate industry and ensuring that all advertising is done in a manner that is clear and straightforward for consumers.

In contrast, the other options do not comply with the necessary advertising standards. The idea that the trade name does not have to appear in advertising contradicts the principles of transparency, while inconspicuous display or emphasizing only the phone number and address would fail to provide sufficient visibility for the agency to be identified by potential clients. Thus, displaying the trade name prominently is essential for effective and compliant real estate advertising.