You plan to deploy a Lync Server 2013 infrastructure.
You plan to use a Microsoft SQL Server database mirror that has a witness.
A database administrator gives you a list of five servers that you can use for the deployment. The servers are configured as shown in the following table.

You need to identify which servers you must use for the SQL Server backend.
Which servers should you identify?

A.
· SQL2 and SQL3 for the mirror
· SQL5 for the witness

B.
· SQL1 and SQL4 for the mirror
· SQL5 for the witness

C.
· SQL2 and SQL3 for the mirror
· SQL4 for the witness

D.
· SQL1 and SQL4 for the mirror
· SQL2 for the witness

Explanation:
http://technet.microsoft.com/en-us/library/gg398990.aspx