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.