Which statement best describes AR 385-63/MCO 3570.1?

The statement that AR 385-63/MCO 3570.1 integrates Marine Corps and Army range policies is correct because this document is designed to provide a unified framework and guidance that applies to both military branches. It consolidates safety, operational, and training protocols to ensure consistency and interoperability between Army and Marine Corps operations. This integration is crucial for joint training exercises and missions, where both branches may operate in the same environments and require standardized safety measures and procedures.

The other options do not accurately reflect the nature of AR 385-63/MCO 3570.1. It is not a purely Army regulation, as it also includes Marine Corps directives. Additionally, it is not limited to Marine Corps training only, as it encompasses policies applicable to both branches. Finally, while some aspects of the regulation may touch on civilian aspects, it is not primarily focused on governing civilian shooting ranges, which usually have their own regulations and oversight.