Final answer:
Class G airspace is the correct answer, representing uncontrolled airspace where pilots fly under visual flight rules without the services of air traffic control and maintain their own separation from other aircraft.
Step-by-step explanation:
The uncontrolled airspace you're referring to is known as Class G airspace. This is the portion of airspace that has not been designated as Class A, B, C, D, or E. In Class G airspace, air traffic control does not provide air traffic services, and pilots fly under visual flight rules (VFR), requiring them to be responsible for their own safety and for maintaining separation from other aircraft. Unlike controlled airspace, which is closely monitored and managed by air traffic control, Class G is basically a 'free flight' area, with less stringent rules and requirements. It's the airspace where student pilots often train and where many recreational flights occur.