What type of airport is publicly owned, has at least 2,500 passengers boarding each year, and receives scheduled passenger service?

The answer that identifies the airport type as publicly owned, serving at least 2,500 passengers boarding annually, and offering scheduled passenger service is commercial service airport. This classification is essential because it highlights the facility's role within public transportation systems, primarily focusing on passenger travel.

Commercial service airports are specifically designed to accommodate and manage a high volume of passenger traffic and are essential for regional connectivity and economic development. Their operation is regulated to ensure safety, efficiency, and compliance with federal standards. Recognizing the minimum passenger boarding requirement establishes the airport's significance in the air transportation network, emphasizing its contribution to meeting public demand for travel.

General aviation airports, while also important, do not typically engage in scheduled passenger service and focus on private aircraft operations. Reliever airports serve to reduce congestion at larger commercial service airports but are not defined by passenger service as their primary function. Cargo service airports, on the other hand, specialize primarily in freight transport rather than passenger travel, further distinguishing them from the commercial service category. Thus, the definition of a commercial service airport encompasses all the attributes mentioned in the question, confirming its correctness.