What is the term for the legal authority granted to a state to exercise control over its airspace?

The correct term for the legal authority granted to a state to exercise control over its airspace is "Sovereignty over airspace." This concept is rooted in international law, particularly in the framework established by the Chicago Convention of 1944, which states that every state has complete and exclusive sovereignty over the airspace above its territory. This principle means that a state has the right to control all activities that occur in its airspace, including the regulation of aviation, air traffic management, and enforcement of safety laws.

In contrast to the correct answer, "Air Traffic Control" refers specifically to the service that manages the flow of aircraft in the airspace and on the ground, ensuring safety and efficiency, rather than the broader concept of sovereignty. "National Sovereignty" relates more generally to a nation's right to govern itself, which can apply across various domains beyond airspace. "Airspace Management" involves the planning and coordination of airspace use but does not encapsulate the legal authority aspect inherent in sovereignty over airspace. Hence, "Sovereignty over airspace" accurately reflects the legal authority context of the question.