You have a DNS server named Server1 that runs Windows Server 2003 Service Pack 2 (SP2). You have two Web servers named Server2 and Server3.The Web servers host an internal Web site that will be accessed by the URL http://www.contoso.com. You need to ensure that requests for www.contoso.com are distributed between Server2 and Server3. What should you do?（）

• A、On each Web server, configure a host header value of www.contoso.com. 
• B、On each Web server, configure a custom HTTP header value of www.contoso.com. 
• C、On Server1, create two host (A) records for www.contoso.com. 
• D、On Server1, create a _roundrobin._tcp.contoso.com service locator (SRV) record for each server that has a port value of 80.