Which feature allows Dell client users to remotely access and manage their systems?

The correct answer highlights Dell's remote management tools, such as Dell Technologies Unified Workspace. These tools are designed to provide comprehensive remote access and management capabilities for Dell clients, enabling IT administrators and users to manage their systems efficiently from any location.

Dell Technologies Unified Workspace integrates various management features, allowing for seamless deployment, updates, and troubleshooting remotely. This capability is essential for organizations that need to maintain their IT infrastructure efficiently, especially in scenarios where employees may be working remotely or in hybrid environments.

The other options, while they may provide some level of support or access, do not deliver the same comprehensive remote management functionality. A built-in firewall function is primarily aimed at security rather than management. Subscription services for remote helpdesk support can assist users but do not replace the essential management capabilities needed to oversee and control systems remotely. Mobile apps may offer some management features, but they are generally more limited compared to the robust set of tools found in a dedicated management solution like the Unified Workspace.