An Engineer Notices That Some SCCP Phones Are Not Displaying

An engineer notices that some SCCP phones are not displaying the correct time, but the phones are registered and working properly. Which three options should be performed in Cisco Unified Communications Manager to fix the phone time issue? (Choose three.)

A) Verify that the device pool has the correct Date/Time Group configured.
B) Ensure that the phone on Time field on the phone configuration page is chosen.
C) Check the CUCM OS Admin page to ensure that NTP servers are accessible
D) Verify that the Date/Time Group has the correct phone NTP reference configured
E) Check the phone NTP reference configuration for configured servers
F) Verify that the Date/Time Group has the correct time zone configured.