A management team at a small office wants to block access to inappropriate websites and...

A content filter is a device or software that blocks or allows access to web pages based on predefined criteria, such as keywords, categories, or ratings. A content filter can also create a log of the blocked or allowed web requests, which can help the management team monitor and audit the web usage of their employees. A content filter is different from the other options because:

A screened subnet is a network segment that is protected by two firewalls, one facing the internet and one facing the internal network. A screened subnet can isolate servers or hosts that need to be accessed from both sides, such as a web server or a bastion host. A screened subnet does not filter web content based on predefined criteria, but rather on network addresses, ports, and protocols.

Port forwarding is a technique that allows a router to forward packets from one port to another port, usually on a different device. Port forwarding can enable remote access to services or applications that are hosted on a private network, such as a web server or a game server. Port forwarding does not filter web content based on predefined criteria, but rather on destination ports and addresses.

An access control list (ACL) is a set of rules that defines which packets are allowed or denied on a network device, such as a router or a firewall. An ACL can filter packets based on source and destination addresses, ports, protocols, and other criteria. An ACL can also create a log of the matched or unmatched packets, which can help the management team troubleshoot and secure their network. An ACL does not filter web content based on predefined criteria, but rather on packet headers and fields.