What is the purpose of this message?

Refer to the exhibit.

You received this debug output to troubleshoot a Cisco IOS MGCP gateway media-related problem
at a customer site. What is the purpose of this message?

A.
The MGCP gateway is responding to an RQNT message from Cisco Unified Communications
Manager to poll the media capabilities on its endpoints.

B.
The MGCP gateway is responding to an AUEP message from Cisco Unified Communications
Manager to poll the media capabilities on its endpoints.

C.
The MGCP gateway is responding to an AUCX message from Cisco Unified Communications
Manager to poll the active calls on its endpoints.

D.
The MGCP gateway is responding to an MDCX message from Cisco Unified Communications
Manager during a call setup.

E.
The MGCP gateway is responding to a CRCX message from Cisco Unified Communications
Manager during a call setup.

Explanation:

See MGCP packet debugging examples and their meanings at the Reference link below.
Sample of Debug MGCP Packets
http://www.cisco.com/c/en/us/support/docs/voice-unified-communications/unifiedcommunications-manager-callmanager/42104-debug-mgcp.html