Which scenario describes a proactive security measure?

Conducting background checks on employees is a proactive security measure because it involves assessing potential risks before any incidents occur. By vetting the backgrounds of individuals before hiring them, an organization can identify any red flags that may indicate a propensity for misconduct or security breaches. This approach helps to mitigate risks and prevent potential security issues before they arise, creating a safer environment for everyone.

The other options describe reactive measures. Installing locks after a break-in, setting up patrols post-incident, and replacing broken security cameras all occur in response to security failures or breaches, rather than attempting to prevent them beforehand. Proactive measures are essential for establishing a strong security foundation and minimizing vulnerabilities in any organization.