What altitude begins the inner circle of Class C airspace?

The correct altitude that begins the inner circle of Class C airspace is 2,500 feet AGL (Above Ground Level). Class C airspace typically consists of a two-tiered structure, which includes an inner circle, a shelf, and an outer area. The inner circle, which is generally centered around the airport, extends from the surface up to 4,000 feet AGL. In this configuration, the inner circle begins at 2,500 feet AGL and is specifically designed to provide controlled airspace for aircraft operating in close proximity to an airport, allowing for safe and organized air traffic flow.

This structure helps manage the transition between different types of airspace and ensures that pilots can operate safely while adhering to specific regulations that govern Class C airspace, including communication protocols with air traffic control. Understanding these altitudes and the layout of Class C airspace is essential for pilots when navigating in and around airport environments.