Your network contains an Active Directory domain named contoso.com. The domain contains two domain controllers named DC1 and DC2 that run Windows Server 2008 R2.DC1 hosts a primary zone for contoso.com. DC2 hosts a secondary zone for contosto.com.You need to ensure that DNS zone data is encrypted when the data replicates across the network. DC2 must provide authoritative responses to client computers.What should you do？（）

• A、Configure the contoso.com zone to use DNSSEC
• B、Create a new delegation in the contoso.com zone
• C、Modify the zone transfer settings of the contoso.com zone
• D、Convert the contoso.com zone to an Active Directory-integrated zone