Security groups are used to manage access permissions to network resources, ensuring only authorized HR department members can access the shared materials. * Why Not B (Audit logs): Audit logs monitor activity but do not restrict access. * Why Not C (Time-of-day access): Time-of-day access limits when users can access resources but doesn't specify user permissions. * Why Not D (Print server): A print server manages print jobs but does not control file access. CompTIA A+ Exam Reference: Core 2 (220-1102), Section 2.5, access control and permissions.