You work as a network administrator for Certkiller .com. You run the command:
ping Certkiller 3 and after a short time you receive the response: no answer from Certkiller 3 Which is a possible cause of this message?

A.
Your local network interface is configured as down.

B.
The interface on Certkiller 3 has been configured as down.

C.
Your IP address is not the /etc/hosts or Certkiller 3.

D.
Your local system is unable to resolve the IP address for Certkiller 3.