Which security measure is most associated with combating unauthorized USB device usage?

The USB Control Policy is a security measure specifically designed to manage and restrict the use of USB devices within an organization. This policy can define which devices are allowed, control user access to USB ports, and enforce rules regarding data transfer to prevent unauthorized access and data exfiltration. By implementing a USB Control Policy, organizations can mitigate the risks associated with plug-and-play devices, such as malware infections or data breaches caused by unauthorized USB drives being connected to company systems.

While data encryption protocols are instrumental in protecting data at rest and in transit, they do not specifically address the risks posed by unauthorized USB devices. Similarly, network firewalls are essential for monitoring and filtering incoming and outgoing network traffic but do not specifically target USB device usage. VPN services are crucial for secure remote connections and protecting data during transmission over unsecured networks but do not mitigate risks related to local USB device connections.

Therefore, the most effective measure for combating unauthorized USB device usage is a USB Control Policy, as it directly regulates how USB ports and devices are utilized within an organization's IT infrastructure.