You manage your existing virtual environment by using Microsoft System Center Virtual Machine Manager (VMM) 2008 R2. You are designing a highly available Hyper-V solution. You need to minimize the downtime of virtual machines (VMs) during maintenance periods.
What are two possible ways to achieve this goal? (Each answer presents a complete solution. Choose two.)

A.
Create a host group that contains Server1 and Server2, and place each VM on NFS storage.

B.
Create a Hyper-V failover cluster of Server1 and Server2, and place each VM on a separate shared iSCSI logical unit number (LUN).

C.
Create a Hyper-V failover cluster of Server3 and Server4, and place all VMs on a single Fibre Channel logical unit number (LUN).

D.
Create a Hyper-V failover cluster of Server3 and Server4, and place all VMs on a single iSCSI logical unit number (LUN) that is configured as a Cluster Shared Volume (CSV).