Your environment includes a Windows Server 2008 R2 Hyper-V failover cluster. You manage the virtual environment by using Microsoft System Center Virtual Machine Manager （VMM） 2008 R2.  You plan to perform maintenance on the Hyper-V failover cluster. You need to complete the maintenance on the failover cluster while maximizing the uptime of the virtual machines （VMs）.  What should you do prior to starting maintenance on each cluster node？（）

• A、Use Failover Cluster Manager to pause the cluster node
• B、Use Failover Cluster Manager to perform a quick migration of all VMs to another cluster node
• C、Use VMM to place the cluster node in maintenance mode
• D、Use VMM to pause all VMs and move them to another cluster node