Your highly available virtual environment includes Windows Server 2008 R2 Hyper-V servers. You are developing a strategy to apply Hyper-V updates. You need to ensure that you can deploy updates while minimizing server downtime. What should you do on each Hyper-V server？（）
- AMigrate the VMs， apply the update to the Hyper-V server， apply the update to each VM， and then migrate the VMs back to the Hyper-V server
- BPause the VMs， apply the update to the Hyper-V server， and then apply the update to the VMs
- CApply the update to the Hyper-V server， and then apply the update to the VMs
- DTake a snapshot of the VMs， and then apply the update to the Hyper-V server