Your company has a main office and a branch office. Your network contains a single Active Directory domain. The functional level of the domain is Windows Server 2008 R2. An Active Directory site exists for each office. All servers run Windows Server 2008 R2. You plan to deploy file servers in each office. You need to design a file sharing strategy to meet the following requirements： èUsers in bothoffices must be able to access the same files. èUsers in both offices must use the same Universal Naming Convention （UNC） path to access files. èThe design must reduce the amount of bandwidth used to access files. èUsers must be able to access files even if a server fails. What should you include in your design？（）

A stand-alone DFS namespace that uses replication.
B. A domain-based DFS namespace that uses replication.
C. A multi-site failover cluster that contains a server located in the main office and another server located in the branch office.
D. A Network Load Balancing cluster that contains a server located in the main office and another server located in the branch office.