Screening router inspects traffic through examining:

A.
message header.

B.
virus payload

C.
message content

D.
attachment type

E.
None of the choices.

Explanation:
The simplest and almost cheapest type of firewall is a packet filter that stops messages with inappropriate
network addresses. It usually consists of a screening router and a set of rules that accept or reject a message
based on information in the message header.