Which firewall makes access decisions based only on addresses and port numbers?

A.
Circuit-based proxy

B.
Application-based proxy

C.
Stateful

D.
Dual-homed

Explanation:
A circuit-level proxy firewall looks at header information to make
decisions on whether a packet is deemed acceptable for access. This is a different
approach than application-level firewalls, which look at the information within the
payload of the packet. A stateful firewall maintains a state table to keep track of
each communication dialog taking place between systems and makes access decisions
based on the information within this table.