What is required to configure NTP on a Cisco Unified Communications Manager publisher to support SIP phones?

A.
Configure Phone NTP References in Cisco Unified CM Administration.

B.
Configure the NTP server in Cisco Unified OS Administration

C.
Configure the NTP server in Cisco Unified CM Administration.

D.
Configure time in Cisco Unified OS Administration.

E.
Restart the Unified Communications Manager services for the publisher and subscribers on the Unified CallManager Serviceability page