An access control list (ACL) is used to:

• A. Specifies which users or systems have permissions for a resource.
• B. Defines backup schedules for critical systems.
• C. Lists approved software for use on the network.
• D. Sets password expiration policies.

Answer: (A)

An access control list defines who can access a resource and what actions they’re allowed to perform. It attaches a list of principals (users or systems) to specific permissions like read, write, or execute, enforcing who is authorized to interact with that resource. This differs from backup schedules, software approval lists, or password expiration policies, which govern data protection timing, what software is allowed, and authentication rules, respectively. So an ACL’s purpose is precisely to specify which users or systems have permissions for a resource.