When configuring a Firebox wireless device, what is one option for external network access?

Selecting the option to 'Enable wireless client as external interface' allows the Firebox wireless device to use the wireless network interface for external network access. This configuration is crucial because it enables wireless clients to communicate with external networks, such as the internet, while ensuring that the Firebox maintains control over the traffic. By designating the wireless interface as an external interface, clients connected to the wireless network can securely access resources beyond the local network.

Additionally, this setup can be essential in environments where a wired connection isn't feasible or when mobility is necessary. It supports the flexible use of Wi-Fi for internal users while maintaining security protocols through the Firebox appliance. This approach ultimately enhances connectivity options without restricting access to the broader network.

The other options focus on different aspects of network configuration and do not directly align with the requirement of providing external network access via the wireless device. The choice to enable only wired connections limits flexibility and does not apply when considering the intent of external Wi-Fi access. Configuring a VPN connection is more about secure communications rather than enabling external access directly through the wireless interface. Disabling DHCP would complicate network configurations and user connectivity, contrary to the goal of ensuring effective external network access.