Your company has an Active Directory Domain Services (AD DS) domain. All servers run Windows Server 2008 R2. All client computers run Windows 7. You use Microsoft Enterprise Desktop Virtualization (MED-V). You need to prepare the MED-V server for cluster mode. What should you do?（）

A. Copy the ConfigurationServer folder to a network share.
B. Add the Failover Clustering feature to the MED-V server.
C. Add the Network Load Balancing (NLB) feature to the MED-V server.
D. Migrate the MED-V server to a highly available virtual machine (HAVM).