Which of the following is an allowable use of airport revenue?

Airport revenue must be used in accordance with regulations that ensure that the funds support the operation, maintenance, and development of the airport and its services. Supporting community activities that are related to the airport is an allowable use of airport revenue because it fosters good relationships with the local community, enhances the airport's public image, and promotes the airport's role in supporting the local economy and environment. These activities can include sponsorship of local events, educational outreach programs, or initiatives that enhance community awareness about the airport’s operations and benefits.

In contrast, the other options involve uses of revenue that do not directly support the airport's operations or mission. Lobbying for non-aviation-related regulations does not fall under acceptable uses, as these funds must be focused on aviation and airport-related expenses. Payments to private companies for unrelated services would similarly divert funds from necessary airport operations, while investing in off-airport real estate takes resources away from the core responsibilities of the airport facility itself. Therefore, supporting community activities connected to the airport aligns with the principles governing airport revenue use.