Comprehensive and Detailed Explanation:
Thenetstatoutput shows thatmultiple ports are open, includingTelnet (23), FTP (20), and TFTP (69), which are potential security risks.Disabling unused portsminimizes the attack surface, reducing security vulnerabilities.
Breakdown of Options:
* A. Disable the unused ports-Correct answer.Unused portsshould be closedto prevent unauthorized access.
* B. Enforce access control lists- ACLs help control access but donot disable unnecessary services.
* C. Perform content filtering- Content filtering controlsweb traffic,not port security.
* D. Set up a screened subnet- ADMZ (screened subnet)improves security but doesnot address open ports.