Hotspot Question
Your network contains an Active Directory forest named contoso.com. The forest contains an Active
Directory Federation Services (AD FS) farm. You install Windows Server 2016 on a server named
Server2. You need to configure Server2 as a node in the federation server farm. Which cmdlets
should you run? (To answer, select the appropriate options in the answer area.)
Answer: 
I think the exhibit is wrong.
Install-AdfsFarm creates the first node of a new federation server farm.
https://docs.microsoft.com/en-us/powershell/module/adfs/install-adfsfarm?view=win10-ps
but “The forest contains an Active Directory Federation Services (AD FS) farm” and “You need to configure Server2 as a node in the federation server farm”
So I think that the missing cmdlet is Add-AdfsFarmNode.
Add-AdfsFarmNode adds this computer to an existing federation server farm.
https://docs.microsoft.com/it-it/powershell/module/adfs/Add-AdfsFarmNode?view=win10-ps