Final answer:
The New York State Department of Financial Services is the agency that registers mortgage brokers in New York.
Step-by-step explanation:
The New York agency that registers mortgage brokers is the New York State Department of Financial Services. This agency regulates and supervises the sale of securities and the brokers, dealers, and bankers who sell them. It ensures that mortgage brokers in New York comply with the state's laws and regulations to protect consumers and promote fair and transparent practices in the mortgage industry.