What is defined as "Controlled Airspace"?

Controlled airspace is defined as airspace in which air traffic control (ATC) has authority over aircraft operations, ensuring safe and organized flight activities. This type of airspace is typically established to manage traffic, provide separation between aircraft, and enhance safety, especially in congested areas. Within controlled airspace, pilots are required to follow specific rules and procedures, including communication with ATC, which helps maintain an orderly flow of air traffic.

The other options do not accurately represent what controlled airspace is. The option regarding airspace reserved for military operations refers to a different category of airspace, which may be restricted or prohibited but is not solely controlled by ATC for civilian flight operations. The mention of airspace used primarily for Visual Flight Rules (VFR) flights pertains to uncontrolled airspace, where pilots fly based on visual reference rather than ATC instructions. Lastly, unregulated airspace stands apart from controlled airspace, as it implies there are no ATC restrictions or authority over aircraft in that region, allowing more freedom but less oversight.