Your network contains an Active Directory domain named contoso.com. The domain contains a  member server named Hyperv1 and a domain controller named DC1. Hyperv1 has the Hyper-V  server role installed. DC1 is a virtual machine on Hyperv1. Users report that the time on their client computer is incorrect. You log on to DC1 and verify that the time services are configured correctly. You need to prevent time conflicts between the time provided by DC1 and other potential time sources. What should you configure？ To answer， select the appropriate object in the answer area.

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