What color must socks be when worn with the APFU?

The correct answer is that socks worn with the Army Physical Fitness Uniform (APFU) must be black or white. This guideline ensures a standardized appearance among service members during physical training and reflects military discipline. By maintaining uniformity in sock color, it enhances the overall look of the APFU and promotes a sense of belonging and professional pride.

In the context of military dress codes, adhering to specific color regulations helps maintain a cohesive identity, especially during physical training sessions where camaraderie and teamwork are essential. The choices of other colors do not align with these standards, which is why they are not correct options.