Your company has two data centers.  Each data center contains a perimeter network.  Your network contains an Exchange Server 2010 organization.  You plan to deploy Exchange Server 2010 Edge Transport servers in the perimeter networks.  You need to recommend a solution for the Edge Transport servers that meets the following requirements：.Distribute inbound e-mail messages across all Edge Transport servers  .Ensure that users receive inbound e-mail messages if an Edge Transport server fails  .Ensure that users receive inbound e-mail messages if a single data center network becomes unavailable.Minimize costs  What should you recommend？（）

• A、In each perimeter network， deploy one Edge Transport server. Implement failover clustering.
• B、In each perimeter network， deploy two Edge Transport servers. Implement failover clustering.
• C、In each perimeter network， deploy one Edge Transport server. Configure a mail exchange （MX） record for each server.
• D、In each perimeter network， deploy two Edge Transport servers. Configure a mail exchange （MX） record for each server.