In an AD DS forest you deployed a read-only domain controller (RODC1). You need to make User1 a local administrator on RODC1 using the principle of least privilege. Which tool should you use?

Computer Management is the correct tool because it provides a graphical interface to manage local users and groups on a specific server, including an RODC. You can use it to add User1 to the local Administrators group on RODC1, adhering to the principle of least privilege by granting local administrative rights only where needed. dsmgmt.exe is a command-line tool for managing Active Directory objects, not local users and groups on a specific server. Local Users and Groups is a snap-in within Computer Management, so while it's part of the solution, Computer Management is the overarching tool. net user is a command-line tool for managing local user accounts, but it's less comprehensive than Computer Management for group management and doesn't directly address adding a domain user to a local group in the most straightforward way for this scenario.