Harold wants to set up a firewall on his network but is not sure which one would be the most appropriate. He knows he needs to allow FTP traffic to one of the servers on his network, but he wants to only allow FTP-PUT. Which firewall would be most appropriate for Harold? needs?

A.
Circuit-level proxy firewall

B.
Packet filtering firewall

C.
Application-level proxy firewall

D.
Data link layer firewall