A network administrator needs to prevent users from accessing the account department records. All users are connected to the same Layer 2 device and access the Internet through the same router. Which of the following should be implemented to segment the accounting department from the rest of the users?

1. Implement VLANs and an ACL.
2. Install a firewall and create a DMZ.
3. Create a site-to-site VPN.
4. Enable MAC address filtering.