In computing, a stateful firewall (any firewall that performs stateful packet inspection (SPI) or stateful inspection) is a firewall that keeps track of the state of network connections (such as TCP streams, UDP communication) traveling across it. You have been studying stateful packet inspection and want to perform this security technique on the network. Which device will you use to BEST utilize stateful packet inspection?

A.
Switch

B.
Hub

C.
IDS

D.
Firewall