A security analyst noticed a colleague typing the following command:
‘Telnet some-host 443’
Which of the following was the colleague performing?

A.
A hacking attempt to the some-host web server with the purpose of achieving a distributed
denial of service attack.

B.
A quick test to see if there is a service running on some-host TCP/443, which is being routed
correctly and not blocked by a firewall.

C.
Trying to establish an insecure remote management session. The colleague should be using
SSH or terminal services instead.

D.
A mistaken port being entered because telnet servers typically do not listen on port 443.