802.1X is a network authentication protocol commonly used in enterprise environments. If the user cannot connect to the office wireless network but can connect at home, the issue is likely related to the 802.1X certificate required for authentication. Installing or updating the certificate will resolve the issue. Why Not B (Check the wireless router settings): If other users can connect to the network, this step is unnecessary. Why Not C (Update the wireless driver): Driver updates might resolve connectivity issues but are unrelated to 802.1X certificate authentication. Why Not D (Disable the Windows firewall): The firewall does not affect 802.1X authentication. CompTIA A+ Exam Reference: Core 1 (220-1101), Section 2.6, wireless network authentication.