Which two characteristics of the attack must you understand to configure the attack object?

You have been asked to configure a signature to block an attack released by a security vulnerability reporting agency. Which two characteristics of the attack must you understand to configure the attack object? (Choose two )

A.
the source port of the attacker

B.
a string or regular expression that occurs within the attack

C.
the context where the attack pattern is found within the packet

D.
the IPv4 routing header