You need to ensure that a user named Contoso\\User1 can…

Your network contains an Active Directory domain named contoso.com. All domain controllers run Windows
Server 2012 R2.
In a remote site, a support technician installs a server named DC10 that runs Windows Server 2012 R2. DC10
is currently a member of a workgroup.
You plan to promote DC10 to a read-only domain controller (RODC).
You need to ensure that a user named Contoso\\User1 can promote DC10 to a RODC in the contoso.com
domain.
The solution must minimize the number of permissions assigned to User1.
What should you do?

A.
From Active Directory Administrative Center, pre-create an RODC computer account.

B.
FromNtdsutil, run the local roles command.

C.
FromDsmgmt, run the local roles command.

D.
Join DC10 to the domain. Run dsmod and specify the /server switch.

Explanation:
A staged read only domain controller (RODC) installation works in two discrete phases:
1. Staging an unoccupied computer account
2. Attaching an RODC to that account during promotion