Your virtual environment includes Windows Server 2008 R2 Hyper-V servers. The test and development teams are developing a distributed application.  The application requires a domain controller， a server that runs Microsoft SQL Server， an application server， and a client computer. The application uses pass-through authentication. You need to ensure that at the time of a failure， the test team can reproduce the error and provide the application in the state in which it existed when the error occurred to the development team for continued analysis. You must achieve this goal while minimizing storage requirements.  What should you do？（）

• A、Snapshot and export all servers
• B、Snapshot and export only the application server
• C、Snapshot the application server， and back up the SQL Server database
• D、Snapshot and export only the domain controller and the client computer