Which of the following is not one of the four functions of access control?

• A. Delay, Detection, Alert, and Response
• B. Delay, Detection, Alert
• C. Identification, Authentication, Authorization, and Audit
• D. Notification

Answer: (D)

Access control has four core functions that govern who can access what and how their access is tracked: identification, authentication, authorization, and audit (accountability). Notification isn’t part of that core quartet; it’s about signaling or informing events rather than establishing and enforcing access rights. The other options reflect either a different security framework (such as a physical-security model with delay, detection, and response) or the actual four core access-control functions. So, the item that isn’t one of the four functions is notification.