Which factor is essential when issuing keys in a key control program?

Issuing keys only to those with legitimate requirements is a fundamental principle of an effective key control program. This approach minimizes the risk of unauthorized access to sensitive areas and assets. When keys are distributed exclusively to individuals who have a legitimate need, it ensures that access is controlled and monitored, thereby enhancing overall security.

This practice is crucial in preventing potential security breaches that could occur if keys are given indiscriminately. By limiting key distribution, organizations can also track who has access to specific areas, making accountability easier and improving response times if a security incident occurs. It contributes to maintaining a secure environment while fostering trust among personnel who understand the importance of access control.

The other options generally compromise security. For example, distributing keys to all staff disregards the need for security oversight, sharing keys undermines accountability, and issuing unlimited duplicates creates potential for many unauthorized copies to circulate, leading to an increased risk of theft or loss.