This scenario involves firewall configuration and service accessibility, which falls under the Security domain of the CompTIA Linux+ V8 objectives. The key to resolving this issue is interpreting both the firewall output and the web server status correctly.

The web server output shows that the service is actively listening on TCP port 443, which is the standard port for HTTPS (secure web traffic). The line tcp LISTEN 0 4096 *:443 *:* confirms that the web server is running properly and is ready to accept incoming connections on port 443 from any interface. This indicates that the problem is not with the web server configuration itself.

However, the firewall output clearly shows that incoming connections to port 443 are being blocked. The rules 443/tcp DENY Anywhere and 443/tcp (v6) DENY Anywhere (v6) indicate that the Uncomplicated Firewall (UFW) is explicitly denying HTTPS traffic for both IPv4 and IPv6. As a result, external clients cannot establish a secure connection to the server, even though the service is running correctly.

To resolve this issue securely and correctly, the administrator must remove the firewall rule that denies HTTPS traffic. Option C, ufw delete deny https/tcp, directly removes the blocking rule while preserving the rest of the firewall configuration. This aligns with Linux+ best practices, which emphasize making precise firewall changes rather than disabling security controls entirely.

The other options are incorrect. Option A, ufw disable, would completely turn off the firewall, creating a significant security risk. Option B, ufw allow 80/tcp, only opens HTTP traffic on port 80 and does not resolve HTTPS connectivity issues. Option D, ufw allow 4096/tcp, incorrectly attempts to open an internal socket backlog value rather than a valid service port.

Therefore, the correct and most secure solution is C.