Which regulation outlines the security of arms, ammo, and explosives?

The correct answer is based on the fact that AR 190-11 specifically addresses the security of arms, ammunition, and explosives within the Army. This regulation establishes the policies and procedures to ensure proper storage, handling, and accountability of these materials to prevent unauthorized access and ensure safety. It outlines the security measures necessary for various types of facilities, including arms rooms, and the duties of personnel involved in safeguarding these critical items.

In contrast, the other choices address different areas of Army operations. AR 190-10 deals with methods for maintaining order and discipline in military operations and specifies provisions for civil disturbances. AR 600-8-105 focuses on military operations and the management of personnel actions and related administrative matters, while AR 350-1 centers on Army training and training support. These regulations do not specifically tackle the issues of security related to arms, ammunition, and explosives, which is why they do not apply in this context.