Which of the following types of firewalls would BEST protect a network from an internet attack?

A.
Screened subnet firewall

B.
Application filtering gateway

C.
Packet filtering router

D.
Circuit-level gateway

Explanation:
A screened subnet firewall would provide the best protection. The screening router can be a
commercial router or a node with routing capabilities and the ability to allow or avoid traffic between
nets or nodes based on addresses, ports, protocols, interfaces, etc. Application-level gateways are
mediators between two entities that want to communicate, also known as proxy gateways. The
application level (proxy) works at the application level, not just at a package level. The screening
controls atthe package level, addresses and ports, but does not see the contents of the package.
A packet filtering router examines the header of every packet or data traveling between the internet
and the corporate network.