Your network contains an Active Directory domain named contoso.com. The domain
contains two domain controllers.
The domain controllers are configured as shown in the following table.

In the perimeter network, you install a new server named Server1 that runs Windows Server
2012 R2. Server1 is in a workgroup.
You need to perform an offline domain join of Server1 to the contoso.com domain.
What should you do first?

A.
Run the dsadd.exe command.

B.
Run the djoin.exe command.

C.
Transfer the infrastructure master role to DC1.

D.
Transfer the PDC emulator role to DC1.

Explanation:
The djoin command should be used for offline join in the perimeter network.
References:
Training Guide: Installing and Configuring Windows Server 2012 R2: Chapter 5: Active
Directory Administration, p. 187
Training Guide: Installing and Configuring Windows Server 2012 R2: Chapter 4: Deploying
Domain Controllers, Lesson 2: Deploying domain controllers using Server Manager, p. 157