Which of the following commands would block all ICMP packets from the host 1.2.3.4 coming to your machine?
A.
iptables -A INPUT -s 1.2.3.4 -p icmp -j DROP
B.
iptables -A INPUT -s 1.2.3.4 -p icmp -j DENY
C.
iptables -A OUTPUT -s 1.2.3.4 -p icmp -j DENY
D.
iptables -A OUTPUT -s 1.2.3.4 -p icmp -j DROP