When configuring the NTP server with MSCS clustered virtual machines, the best practice is:

A.
Synchronize domain controllers and cluster nodes with a common NTP server and enable host
based time synchronization in the guest.

B.
Enable host based time synchronization for domain controllers, cluster nodes and guest virtual
machines.

C.
NTP should not be used in conjunction with MSCS clustered virtual machines.

D.
Synchronize domain controllers and cluster nodes with a common NTP server, and disable host
based time synchronization in the guest.

Explanation:
Setup for Failover Clustering and Microsoft Cluster Service ESX 4.0 ESXi 4.0 vCenter
Server 4.0, page 10.
Synchronize domain controllers and cluster nodes with a common NTP server, and
disable host based time synchronization when using clustering in the guest.