What extends at 1,000 yards/meters from the HVA?

The correct choice is the reaction zone, which is specifically defined in the context of security for High-Value Assets (HVA). The reaction zone extends out to 1,000 yards/meters from an HVA and is designed to provide a buffer zone within which command and control measures can be enacted. In this area, protective actions can be coordinated quickly should a threat be perceived or identified.

This zone is crucial because it allows for the timely response and maneuvering of security forces to neutralize potential threats before they can reach the HVA. The designation of specific zones—such as the engagement zone or the threat zone—serves different purposes in security protocols and does not have the same boundaries or functions as the reaction zone. Understanding these distinctions helps ensure optimal protective measures are in place around HVAs.