In which type of airspace are aircraft not completely prohibited but are subject to certain operational rules?

The correct choice is based on the nature of restricted airspace and its operational rules. In restricted airspace, aircraft operations are not entirely prohibited; however, they must adhere to specific regulations and limitations. This airspace is designated for activities that may be hazardous to non-participating aircraft, such as military training or aerial gunnery.

Pilots flying in or near restricted airspace must be aware of the restrictions and may need permission from the appropriate authority to operate in that area. This ensures the safety of all aircraft, while still allowing for regulated access under certain conditions.

Controlled airspace, while having operational rules, typically allows for a wider range of aircraft operations based on air traffic control services. Special use airspace can encompass various zones with different restrictions but not all special use airspace inherently requires adherence to operational rules that are as stringent as those in restricted airspace. Class G airspace, or uncontrolled airspace, is where the least regulation applies, with pilots of VFR (Visual Flight Rules) flights operating largely independently. Thus, restricted airspace stands out in that it permits operations but with defined constraints.