Which of the following is NOT mentioned as part of military postal operations?

Contractual Services is the correct answer since it is not typically associated with military postal operations in the same way that the other options are. Military postal operations primarily include systems and facilities directly involved in the handling and processing of mail for military personnel.

Military Post Offices are essential hubs that facilitate the delivery and receipt of mail, ensuring that service members can communicate with their families and maintain contact with the outside world. Aerial Mail Terminals play a crucial role in the expedited transfer of mail through air transport, which is particularly important for reaching remote locations. Official Mail Centers are responsible for processing and distributing official correspondence, further illustrating the structured network of military postal operations.

In contrast, while contractual services may play an indirect role in supporting military functions, they are not a core component of the established military postal operations framework.