Question: What is the primary purpose of the CSC-18 reference point between migration management servers in different Mission Critical (MC) systems?
Option 1: To facilitate the exchange of SIP authentication information for MC service User Equipment (UEs) migrating between MC systems.
Option 2: To manage Quality of Service (QoS) parameters for MC services across different network domains.
Option 3: To enable direct communication between MC UEs in separate MC systems for group calls.
Option 4: To synchronize alarm messages and event notifications among MC system administrators.
Explanation: The CSC-18 reference point is specifically utilized for the exchange of SIP (Session Initiation Protocol) authentication information. This process is crucial for ensuring seamless migration of Mission Critical service UEs between different MC systems, maintaining security and continuity of service.