A group policy object or GPO can be configured to implement security parameters of a Windows domain, among other things. Different organizations have different security needs, and their GPO settings can vary. Try to imagine your current workplace or a past one where you think a GPO would work well (maybe it even used them).
What features do you think you would set up in the GPO?
Consider things like passwords policies, allowing someone to log onto a server, and so on.
Talk about a few settings you like and why they would work, and maybe one you do not think would be useful at all. Do not forget to explain why.