Active Subdomain Enumeration

Hi all I’m stuck again, but Now, on literally the next question which is:
What is the FQDN of the IP address

Someone, please help! No spoilers plz.

You need found out the “Pointer”. Its all that will say.

Wait what do you mean? There is no pointer given if there’s one that is hidden how do you find it? is there a command I can execute?