Your network contains a server named Server1 that runs Windows Server 2008 R2 Service Pack 1
(SP1). Server1 contains two dynamic disks named Disk1 and Disk2. Disk1 has a volume that contains
critical dat a. Disk2 does not contain a volume. You need to create a mirror of the volume on Disk1.
Which Diskpart command should you run?

A.
format

B.
retain

C.
merge vdisk

D.
attributes

E.
add

F.
break

G.
GPT

H.
compact vdisk

I.
recover J. active K. rescan L. extend
M.
detach vdisk
N.
offline
O.
repair
P.
automount
Q.
remove
R.
online
S.
filesystems
T.
assign
U.
list
V.
expand vdisk
W.
create
X.
attach vdisk

Explanation:
Mirrors the simple volume with focus to the specified disk. Add disk=<n> [align=<n>] [wait] [noerr]
To create a mirror of the volume with focus on disk 2, type: Add disk=2
http://technet.microsoft.com/en-us/library/cc754384(v=ws.10).aspx