How are Class G airspaces characterized?

Class G airspaces are characterized as uncontrolled airspace, which means that air traffic control does not provide mandatory guidance for aircraft operating within this airspace. Pilots flying in Class G airspace must operate under visual flight rules (VFR) and follow a basic set of rules established by regulations, which include maintaining visual separation from other aircraft and complying with certain altitude and visibility requirements. This setup allows for a more flexible flying experience, particularly beneficial for general aviation pilots who may not require the level of oversight provided in controlled airspaces.

The other options describe characteristics that do not apply to Class G airspace. Controlled airspace with mandatory ATC guidance reflects the nature of Class B, C, or D airspaces, where ATC services are required. Airspace specifically reserved for commercial airlines pertains to Class A airspace, where IFR (Instrument Flight Rules) operations are mandatory and primarily involve airline traffic. Restricted areas for military use are designated airspaces that limit civilian access, which does not align with the characteristics of Class G airspace.