Your network contains an Active Directory Domain Services (AD DS) domain.

In the Administering Win dows Server Hybrid Core Infrastructure materials for AD DS operations, the time service hierarchy is tied to FSMO roles. The guide states that “the domain controller holding the PDC Emulator role acts as the authoritative time source for the domain; other DCs in the domain synchronize time from the PDC emulator, and domain members synchronize from their logon DCs.” For multi-domain forests, it further clarifies that “the PDC Emulator in the forest root domain is the authoritative source for the forest and s hould be configured to sync with an external, reliable NTP source.”

Regarding management tools, the exam guide specifies that “domain-wide FSMO roles ( RID , PDC Emulator , and Infrastructure ) are transferred by using Active Directory Users and Com puters : right-click the domain, choose Operations Masters , and select the relevant tab.” By con trast, “ Schema Master is managed with the Active Directory Schema snap-in and Domain Naming Master with Active Directory Domains and Trusts .”

Therefore, to make DC3 the authoritative time server for the domain, you must transfer the PDC Emulator role to DC3 and perform the transfer using Active Directory Users and Computers (ADUC) via the Operations Masters dialog.