Your network consists of an Active Directory forest that contains two domains. All servers run  Windows Server 2008 R2. All domain controllers are configured as DNS servers.     You have a standard primary zone for dev.contoso.com that is stored on a member server.     You need to ensure that all domain controllers can resolve names from the dev.contoso.com  zone.     What should you do（）

• A、On the member server， create a stub zone.
• B、On the member server， create a NS record for each domain controller.
• C、On one domain controller， create a conditional forwarder. Configure the conditional forwarder to replicate to all DNS
• D、On one domain controller， create conditionals forwarder. Configure the conditional forwarder to replicate to all DNS