The correct answer is C. Switch the NIC settings from manual to automatic , which allows the computer to obtain an IP address dynamically from the DHCP server. When a static IP address is no longer required, reverting the network configuration to DHCP ensures the system integrates properly with the current network design.

According to the Quentin Docter – CompTIA A+ Complete Study Guide , DHCP simplifies network management by automatically assigning IP addresses, subnet masks, gateways, and DNS settings. Leaving a static IP in place can cause address conflicts or connectivity issues, especially when the device is repurposed.

The Travis Everett & Andrew Hutz – All-in-One Exam Guide explains that DHCP reservations are used when a device must always receive the same IP address, which is unnecessary in this scenario. Creating exclusions or manually changing the static IP does not meet the requirement to remove static addressing altogether.

The Mike Meyers / Mark Soper Lab Manual reinforces that switching the NIC to automatic configuration is the correct way to return a system to standard network operation and avoid manual IP management.

Because the static IP is no longer needed, enabling DHCP by setting the NIC to automatic configuration is the correct solution, making C the correct answer.