You have a server named Data1 that runs a Server Core Installation of Windows Server 2012 R2 Standard.
You need to configure Data1 to run a Server Core Installation of Windows Server 2012 R2 Enterprise. You
want to achieve this goal by using the minimum amount of administrative effort.
What should you perform?

A.
a clean installation of Windows Server 2012

B.
an offline servicing by using Dism

C.
an online servicing by using Dism

D.
an upgrade installation of Windows Server 2012

Explanation:
Training Guide: Installing and Configuring Windows Server 2012 R2: Chapter 2: Deploying Servers, p. 44
Exam Ref 70-410: Installing and Configuring Windows Server 2012 R2: Chapter 1: Installing and Configuring
Servers, p. 19-22