From which regulation does the Captain of the Port derive his authority?

The Captain of the Port derives authority primarily from 33 CFR 1.01-30, which encompasses the broad regulatory framework governing the U.S. Coast Guard's activities, including those related to marine safety, security, and environmental protection. This section outlines the general powers and responsibilities of the Coast Guard and its officers, including the Captain of the Port, establishing their jurisdiction and the ability to enforce various maritime laws.

While other choices may pertain to specific regulations or areas within the Coast Guard's authority, they do not provide the comprehensive scope of authority and responsibilities that 33 CFR 1.01-30 does. This regulation is foundational for understanding the broad regulatory powers under which the Captain of the Port operates, enabling actions such as enforcing safety measures, managing waterways, and responding to pollution incidents.