Your network contains an Active Directory forest named local.
You have a Microsoft 365 subscription. You plan to implement a directory synchronization solution that will use password hash synchronization.
From the Microsoft 365 admin center, you verify the contoso.com domain name. You need to prepare the environment foe the planned directory synchronization solution.
What should you do first?
A . From the public DNS zone of contoso.com, add a new mail exchanger (MX) record.
B . From Active Directory Domains and Trusts, add contoso.com as a UPN suffix
C . From the Microsoft 365 admin center, verify the contoso.com domain name.
D . From Active Directory Users and Computers, modify the UPN suffix for all users.
Answer: B
Explanation:
The on-premise Active Directory domain is named contoso.local. Therefore, all the domain users accounts will have a UPN suffix of contoso.local by default.
To enable directory synchronization that will use password hash synchronization, you need to configure the domain user accounts to have the same UPN suffix as the verified domain (contoso.com in this case). Before you can change the UPN suffix of the domain user accounts to contoso.com, you need to add contoso.com as a UPN suffix in the domain.
Reference: https://docs.microsoft.com/en-us/azure/active-directory/hybrid/plan-connect-userprincipalname