Answer:
Sherman Antitrust Act of 1890
Step-by-step explanation:
In this specific scenario, the real estate broker would be in violation of the Sherman Antitrust Act of 1890. This is a federal statute that prohibits activities that restrict interstate commerce and competition in the marketplace. Therefore, by telling the owner that he must list the property with his broker, the agent is preventing the other competitors from having a fair shot at obtaining the listing, making this a violation.