What command is used to signify that the formation is now without arms and is free to move about?

The command that signifies the formation is now without arms and is free to move about is "Fall Out." This command allows Marines to exit the formalities of the formation and engage in activities such as moving to another location, eating, or socializing without the restriction of being in a specific formation or holding their arms.

Using "Fall Out" conveys a clear intention to transition from a structured state to a more relaxed state, which is essential in ensuring that Marines understand they are no longer required to maintain military posture or decorum. This command differentiates between maintaining formation and taking a break where individuals can act freely while remaining vigilant about their surroundings.

In contrast, other options like "Dismantle" might imply taking apart equipment or structures rather than indicating a transition to a more casual state, while "Rest" typically refers to a temporary pause within formations without granting full freedom of movement. "Break Formation" could suggest a similar idea but lacks the established clarity and protocol that "Fall Out" provides in this context.