Which of the following is a critical component of an access control system?

User authentication is indeed a critical component of an access control system because it serves as the primary method through which identification and verification of individuals are achieved before granting them access to secure areas or systems. It ensures that only authorized users can gain entry, which is fundamental to maintaining security.

In an access control system, user authentication typically involves mechanisms such as password protection, biometrics (fingerprints or face recognition), smart cards, or other forms of identity verification. This ensures that the right individuals are accessing the system or facility, thereby preventing unauthorized access and potential security breaches.

While other elements, such as wireless connectivity, may play roles in how the system operates, they do not directly influence the core function of access control, which is to authenticate users. Energy efficiency is more of a consideration regarding the design or operational costs of a system, and remote logging is helpful for tracking access and monitoring, but without robust user authentication, the integrity of the entire access control system would be compromised.