Which Army Regulation pertains to enlisted promotion and reduction?

The regulation that pertains to enlisted promotion and reduction is AR 600-8-19. This Army Regulation specifically outlines the policies and procedures for promotions and reductions within the Army, which includes guidance on eligibility criteria, the promotion process, and the management of enlisted personnel. It serves as a comprehensive resource for commanders and personnel involved in managing the career advancement of enlisted soldiers.

AR 600-8-22 is focused on military awards, AR 600-20 addresses Army leadership and command policies, and AR 600-25 pertains to the Army's policies on the wear of the uniform and individual recognition, none of which directly deal with the promotion and reduction of enlisted soldiers. In contrast, AR 600-8-19 provides detailed instructions on how promotions should be conducted, making it the correct choice for this question.