Question: Which of the following is NOT a primary functional classification group for operations on the Cx interface in the IP Multimedia (IM) Subsystem?
Option 1: Location Management Procedures
Option 2: User Data Handling Procedures
Option 3: Network Element Firmware Update Procedures
Option 4: User Authentication Procedures
Explanation: The correct answer is Option 3 because the primary functional classification groups for Cx interface operations include Location Management, User Data Handling, and User Authentication. Network Element Firmware Update is not among these primary groups.