What should you create on the DNS servers in contoso.com?

Your network contains an Active Directory forest named contoso.com.
You plan to add a new domain named child.contoso.com to the forest.
On the DNS servers in child.contoso.com, you plan to create conditional forwarders that
point to the DNS servers in contoso.com.
You need to ensure that the DNS servers in contoso.com can resolve names for the servers
in child.contoso.com.
What should you create on the DNS servers in contoso.com?

A.
A zone delegation

B.
A conditional forwarder

C.
A root hint

D.
A trust point