Which of the following best describes a preventive control?

A preventive control is fundamentally designed to stop potential threats before they can have any impact on an organization. It involves implementing measures that mitigate risks preemptively, thus protecting assets and reducing vulnerabilities. Examples of preventive controls include firewalls, access control mechanisms, encryption, and employee training programs. By proactively addressing security challenges, these controls aim to prevent incidents from occurring in the first place.

The other options describe different types of controls. For instance, a mechanism that detects threats after they occur is indicative of a detective control rather than a preventive one. Fixing vulnerabilities after they are identified aligns with corrective controls, which respond to issues post-incident. Lastly, a policy that enforces consequences for policy violations reflects an administrative control focused on governance, accountability, and compliance rather than direct prevention of threats.