Identify the level up to which the unknown traffic is allowed into the network stack

In a TCP packet filtering firewall, traffic is filtered based on specified session rules, such as
when a session is initiated by a recognized computer.

Identify the level up to which the unknown traffic is allowed into the network stack.

A.
Level 5 – Application

B.
Level 2 – Data Link

C.
Level 4 – TCP

D.
Level 3 – Internet Protocol (IP)

Explanation:

Reference:
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