Which two features require or may require configuring a SIP trunk? (Choose two.)

A.
SIP gateway

B.
Call Control Discovery between a Cisco Unified Communications Manager and Cisco Unified Communications Manager Express

C.
Cisco Device Mobility

D.
Cisco Unified Mobility

E.
registering a SIP phone

Explanation:
– Trunk Types Used by Special Applications
Call Control Discovery:
– Special trunks configured in Cisco Unified Communications Manager clusters that refer to an SAFenabled network providing Call Control Discovery features.

CCD between CCM and CUCM Express SAF-CCD requires a SIP Trunk or H.323