Your network contains an Active Directory domain named contoso.com.
The domain contains a domain controller named Dc1. DC1 has the DNS Server server role installed.
The network has two sites named Site1 and Site2. Site1 uses 10.10.0.0/16 IP addresses and Site2 uses 10.11.0.0/16 IP addresses.
All computers use DC1 as their DNS server. The domain contains four servers named Server1, Server2, Server3, and Server4.
All of the servers run a service named Service1. DNS host records are configured as shown in the exhibit. (Click the Exhibit button.)

You discover that computers from the 10.10.1.0/24 network always resolve Service1 to the [P address of Server1.
You need to configure DNS on DC1 to distribute computers in Site1 between Server1 and Server2 when the computers attempt to resolve Service1.
What should run on DC1?

A.
dnscmd /config /bindsecondaries 1

B.
dnscmd /config /localnetpriority 0

C.
dnscmd /config /localnetprioritynetmask 0x0000ffff

D.
dnscmd /config /roundrobin 0

Explanation:
A) Specifies use of fast transfer format used by legacy Berkeley Internet Name Domain (BIND) servers. 1 enables
B) Disables netmask ordering.
C) You can use the Dnscmd /Config /LocalNetPriorityNetMask 0x0000FFFF command to use class B ( or 16 bit) for netmask ordering for DNS round robin
D) Disables round robin rotation.
http://technet.microsoft.com/en-us/library/cc737355(v=ws.10).aspx
http://technet.microsoft.com/en-us/library/cc738473(v=ws.10).aspx
http://support.microsoft.com/kb/842197
http://technet.microsoft.com/en-us/library/cc779169(v=ws.10).aspx