Your company has a data center. The data center contains a server that has Exchange
Server 2016 and the Mailbox server role installed. Outlook anywhere clients connect to the
Mailbox server by using the name outlook.contoso.com.
The company plans to open a second data center and to provision a database availability
group (DAG) that spans both data centers.
You need to ensure that Outlook Anywhere clients can connect if one of the data centers
becomes unavailable.
What should you add to DNS?

A.
one A record

B.
two TXT records

C.
two SRV records

D.
one MX record