All client computers in a test environment run Windows 7 Enterprise with Windows XP Mode. You
are planning to publish a new application on a Windows XP Mode virtual machine (VM). You need to
ensure that you can discard all of the changes to the VM by using the least amount of administrative
effort. What should you do?

A.
Merge the disk.

B.
Compact the disk.

C.
Create a fixed-size disk.

D.
Create a differencing disk.

E.
Create a dynamically expanding disk.

F.
Enable Integration Features.

G.
Configure Enable Undo Disks.

H.
Configure the VM network adapter to Not Connected.

I.
Configure the VM network adapter to Internal Network.

J.
Configure the VM network adapter to Shared Networking (NAT).
K.
Configure the VM network adapter to the physical network adapter.

Explanation:
Use Undo Disks Undo Disks is a feature that saves changes to a virtual machine in a separate undo
disk file in case you want to reverse the changes. The Undo Disks setting applies to all virtual hard

disks attached to the virtual machine. When you run a virtual machine that is using Undo Disks, any
changes to a virtual hard disk are temporarily stored in an undo disk (.vud) file, rather than in the
virtual hard disks attached to the virtual machine. As you continue to make changes to a virtual
machine, those changes continue to grow in the undo disk. If you decide to either apply or discard
the changes stored in an undo disk, that action applies to all changes stored in the undo disk—in
other words, you cannot selectively apply or discard changes on an undo disk. To turn the Undo
Disks feature on or off If the virtual machine is running or hibernated, shut it down. For instructions,
see Shut down a virtual machine manually.
1. Open the Virtual Machines folder.
2. Right-click the name of the virtual machine, and then click Settings.
3. In the left pane of Windows Virtual PC Settings, click Undo Disks.
4. In the right pane, click Enable Undo Disks, and then click OK.
After you turn on the Undo Disks feature for a virtual machine, an undo disk stores all the changes
associated with that virtual machine from the time that you start using the feature. These changes
can include data that you add or delete to a virtual machine, updates applied to the guest operating
system or applications, or even the addition or removal of applications. All virtual hard disks
attached to the virtual machine are unaffected by the changes unless you apply the changes. To
delete the undo disk file, you discard all the changes. This effectively leaves the virtual hard disks
intact and eliminates the possibility that the changes will be applied to the virtual hard disk. Refer to
the following steps to apply or delete an undo disk. You also can configure the virtual machine so
you can choose to discard the undo disk when you close the virtual machine. For more information,
see Close a virtual machine. Note. The undo disk file is stored in the same folder as the virtual
machine configuration (.vmc) file.
To apply or delete an undo disk
1. Follow the steps in the previous section to open the Enable Undo Disks setting.
2. In the right pane, click either Apply changes or Discard changes, and then click OK.
http://technet.microsoft.com/en-us/library/ee449453(v=ws.10)