A packet filter can make the decision to forward or drop packages based on:

source IP address, destination IP address

TCP$/$UDP source and destination port numbers

ICMP message type

TCP SYN and ACK bits

status and$/$or connection information

Which type of packet filter is it$?$

a$.$ Stateless packet filter

b$.$ Stateful packet filter

c$.$ Application Gateway

d$.$ only a and $b$

e$.$ only a and $c$

f$.$ only $b$ and $c$

g$.$ only a b$,$ and c