Which of the following identifies thread fasteners and rivets used by the Air Force and Navy?

The identification of thread fasteners and rivets used by the Air Force and Navy is represented by the AN designator, which stands for "Army-Navy." This system was developed to ensure standardization among military branches and provides a uniform way to categorize and identify hardware components necessary for maintenance and repair. Each component under the AN designator is assigned a unique number that denotes its specific dimensions, strength, and material properties, ensuring uniformity and compatibility across different military applications. This standardization is crucial for the reliability and safety of equipment used in the field.

The other designators, while related to fasteners and components, do not specifically correspond to the threading and fastening systems used by both branches. NAS refers to the National Aerospace Standards, which are not exclusively military and encompass a broader range of civilian applications. MS stands for Military Standard, which includes guidelines for hardware but is not as focused on fasteners as AN. FS designates Federal Specifications, which cover various materials and products in government use, but again, it does not specifically focus on fasteners like the AN system does.