When a user tries to initiate an Ad Hoc conference call from an IP phone, this message appears: No Conference Bridge Available. Which two actions resolve this issue? (Choose two.)

When a user tries to initiate an Ad Hoc conference call from an IP phone, this message appears: No Conference Bridge Available. Which two actions resolve this issue? (Choose two.)
A . Make sure that the Join softkey is assigned to the phone.
B . Make sure that a Conference Bridge resource is registered to Cisco Unified Communications Manager.
C . Reset the phone, to re-register resources.
D . Make sure that a Conference Bridge Resource is assigned to the MRGL on the phone that initiates the conference call.

Answer: B,D