You have an Exchange Server 2013 organization. The organization contains four servers in the same Active
Directory site. The servers are configured as shown in the following table.

EXB and EX4 are members of a database availability group (DAG) named DAG1. All users use Microsoft
Outlook 2013 to connect to their mailbox.
You need to recommend a client access solution to ensure that all of the users can connect to their mailbox if
EX1 or EX2 fails.
What should you recommend?

A.
Add a layer 4 hardware load balancer that balances RPC traffic

B.
Add a layer 7 hardware load balancer that balances the traffic on port 443.

C.
Add a layer 7 hardware load balancer that balances RPC traffic.

D.
Replicate all of the databases in DAG1 to both DAG1 members.

Explanation:
In Exchange 2013, RPC over TCP has been disabled. All outlook communications are now through RPC over
HTTP (Outlook Anywhere). This unifies the CAS protocol methods and provides a stable and reliable
connectivity network between clients and server and between CAS and Mailbox Server. It also reduces the
number of namespaces required. It also eliminates end user interruptions. Hence moving mailboxes around in
DAG and moving mailboxes between mailbox databases are now easy.