Your company has a main office and a branch office. The network contains a single Active Directory domain. The main office contains a domain controller named DC1. You need to install a domain controller in the branch office by using an offline copy of the Active Directory database. What should you do first（）
- AFrom the Ntdsutil tool， create an IFM media set.
- BFrom the command prompt， run djoin.exe /loadfile.
- CFrom Windows Server Backup， perform a system state backup.
- DFrom Windows PowerShell， run the get-ADDomainController cmdlet.