CompTIA Network+ Question B-19

A network technician needs to protect IP based servers in the network DMZ from being discovered by an intruder utilizing a ping sweep. Which of the following should the technician do to protect the network from ping sweeps?

A. Block echo replies inbound to the DMZ
B. Disable UDP on the servers
C. Block ICMP at the firewall
D. Disable TCP/IP on the server

Correct Answer: C