Your network contains multiple subnets.
On one of the subnets, you deploy a server named Server1 that runs Windows Server 2012 R2.
You install the DNS Server server role on Server1, and then you create a standard primary zone named
contoso.com.
You need to ensure that client computers can resolve single-label names to IP addresses.
What should you do first?

A.
Create a reverse lookup zone.

B.
Convert the contoso.com zone to an Active Directory-integrated zone.

C.
Configure dynamic updates for contoso.com.

D.
Create a GlobalNames zone.

Explanation:
Although a GlobalNames zone is required in order to resolve single-label names, GNZs must be AD-integrated.
Since this is a standard primary zone (as opposed to an ADDS primary zone), we must first integrate the zone
into Active Directory.

Exam Ref: 70-410: Installing and Configuring Windows Server 2012 R2, Chapter4: Deploying and configuring
core network services, Objective 4.3: Deploy and Configure the DNS service, p.233
http://technet.microsoft.com/en-us/library/cc731744.aspx