An out-of-band management solution is the best answer because it provides an alternate administrative path to network equipment when the normal production network path is unavailable. If a switch becomes unresponsive through SSH, the technician needs a separate management method that does not depend on the same in-band network connectivity. Out-of-band management can use a dedicated management network, console server, cellular connection, modem, or management interface to reach devices during outages or configuration failures.

The CompTIA Network+ N10-009 objectives include network operations, device management, availability, and remote access methods. SSH is an in-band management method when accessed over the production network. If routing, VLANs, ACLs, management services, or switch control-plane functions are affected, SSH may fail. Out-of-band access improves administrative redundancy and supports recovery.

A jump host can centralize administrative access, but it still depends on network connectivity to the switch. An administrative GUI may also fail if management access is unavailable. A physical console cable can work locally, but the question specifically asks for remote administrative redundancy. Therefore, an out-of-band management solution is the best answer.