You need to deploy the Windows 7 installation by using WDS

Your network contains a server that runs Windows Server 2008 R2 and has the Windows Deployment
Services (WDS) server role installed.
You have a .vhd file that contains an installation of Windows 7.
You need to deploy the Windows 7 installation by using WDS.

You want to achieve this goal by using the minimum amount of administrative effort.

What should you do first?

A.
From Disk Management, mount the .vhd file.

B.
From Windows Deployment Services, add a capture image.

C.
Run the imagex.exe command and specify the /export parameter.

D.
Run the wdsutil.exe command and specify the /add-image parameter.

Explanation:
To add a virtual hard disk image to the server
1. Click Start, right-click Command Prompt, and then click Run as administrator.

2. You must create an image group because .vhd images cannot be in image groups with .wim images. To create an image group for the .vhd image, use the following syntax: WDSUTIL /Add-ImageGroup /ImageGroup:<image group name>.
Example: WDSUTIL /Add-ImageGroup /ImageGroup:VHD Image Group

3. To add the .vhd image to the server, use the following syntax (at a minimum): WDSUTIL /Verbose /Progress /Add-Image /ImageFile:<path> /ImageType:Install /ImageGroup:<image group name>.
For differencing disks, the path to the image should be to the .vhd file of the differencing disk and not to the parent disk. Adding the differencing .vhd will add the parent .vhd file to the server, but only the differencing disk will be active (the parent .vhd will be inactive). If the differencing disk is part of chain, choose the last .vhd in the chain. In that case, the immediate parent .vhd and all preceding parent .vhd files in the chain will also be added.
Full syntax: WDSUTIL /add-Image /ImageFile:<.vhd file path> [/Server:<server name>] /ImageType:install [/ImageGroup:<image group name>] [/Filename:<new image file name>] [/UnattendFile:<full path to unattend file>]
Example: WDSUTIL /Verbose /Progress /Add-Image /ImageFile:C:\vhd\WindowsServer2008R2.vhd /Server:MyWDSServer /ImageType:Install /ImageGroup:VHD Image Group

4. Repeat step 3 until you have added all of your .vhd images.

5. If you want to update the description for an image, use the following steps:

a. Run WDSUTIL /Get-ImageGroup /ImageGroup:<image group name> and note the name that the server assigned to the image. To display the full image metadata on each image in the group, append /Detailed.
Example: WDSUTIL /Get-ImageGroup /ImageGroup:VHD Image Group

b. To update the description for an image, use the following syntax where <image name> is the name you noted in the previous step: WDSUTIL /Set-Image /Image:<image name> /ImageType:Install /ImageGroup:<image group name> /Description:<description>.
Example: WDSUTIL /Set-Image /Image:VHD image /ImageType:Install /ImageGroup:VHD Image Group /Description:VHD image for R2

Source: http://technet.microsoft.com/en-us/library/dd363560(WS.10).aspx