Access control refers to?

• A. A unified mechanism for managing user authentication and access to applications and data.
• B. A firewall rule to block all unauthorized traffic.
• C. A tool to monitor VLAN usage.
• D. An encryption standard.

Answer: (A)

Access control is about making sure only the right people can reach the resources they are permitted to use by verifying who they are and what they’re allowed to do. The best answer describes a unified mechanism that manages user authentication and access to applications and data, which is precisely what access control encompasses—centralized policy enforcement across resources.

The other options mix in related security ideas without capturing the core function: a firewall rule blocks traffic but doesn’t govern individual user access to specific apps or data; monitoring VLAN usage is about network visibility rather than who may access resources; an encryption standard protects data content but doesn’t determine permissions or identities.