Your network contains a Hyper-V host named Hyperv1 that runs Windows Server 2012 R2. Hyperv1 has a virtual switch named Switch1. You replace all of the network adapters on Hyperv1 with new network adapters that support singleroot I/O virtualization （SR-IOV）. You need to enable SR-IOV for all of the virtual machines on Hyperv1. Which two actions should you perform？（）

• A、On each virtual machine， modify the Advanced Features settings of the network adapter
• B、Modify the settings of the Switch1 virtual switch
• C、Delete， and then recreate the Switch1 virtual switch
• D、On each virtual machine， modify the BIOS settings
• E、On each virtual machine， modify the Hardware Acceleration settings of the network adapter