What is the radius of the inner circle of Class C airspace centered on a primary airport?

Class C airspace is a specific type of airspace that is designed to manage aircraft operations around busy airports. The inner circle, also known as the core area, of Class C airspace typically has a radius of 5 nautical miles (NM) from the center of the primary airport. This is crucial for maintaining safe separation between arriving and departing traffic and ensuring that pilots, air traffic controllers, and aircraft are able to operate efficiently within this space.

While other options may suggest different radii, the standard radius of 5 NM is what defines the inner circle in Class C airspace, emphasizing the need for structured air traffic management, especially in regions with high traffic volume. This standardization helps ensure that all parties involved in aviation can anticipate and understand the operational environment around the airport.