You are the administrator of your company's DNS servers. The DNS server is located on a member server named xyz$-$dns$1$ in the xyz$.$com Active Directory domain. xyz$-$dns$1$ provides name resolution for the xyz$.$com domain only. Occasionally, you see DNS records for unauthorized computers in the xyz$.$com zone. These computers do not have accounts in the xyz$.$com Active Directory domain.

Which of the following steps should you take to prevent unauthorized computers from registering host records with the DNS server?