Answer:
The correct answer is A)
Step-by-step explanation:
A firewall in the computer science parlance refers to a program that is designed specifically to monitor the inflow and outflow of connectivity traffic. By a predetermined set of rules, it is able to block unwanted connections, suspicious and or malicious connections thus preventing the computer from external attack.
As indicated in the question, there are various types of firewalls.
A Stateful Firewall is one that checks the complete state of network connections. This includes all communication between all incoming connections and internal protocol. So all incoming traffic is first screened and if they demonstrate any semblance of a malicious program or traffic, they are terminated at source.
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