What is a benefit of applying operating system updates to stable client computers?

Applying operating system updates to stable client computers is primarily beneficial for closing existing vulnerabilities. Operating system updates often include security patches that address newly discovered vulnerabilities or weaknesses within the system. By regularly applying these updates, you can significantly reduce the risk of exploitation by malicious entities, thereby enhancing the overall security of the computer.

This practice is essential because vulnerabilities can be targets for attackers looking to gain unauthorized access or compromise sensitive data. Updates often address these potential entry points—effectively "closing the door" that attackers might exploit. Therefore, continuously updating the operating system is a key practice for maintaining a secure computing environment.

The other options do not directly relate to the security benefits derived from software updates. Keeping software licensed, maintaining available server ports, and updating hardware firewalls are all important, but they do not specifically address the need to protect systems from vulnerabilities that can lead to security breaches.