Question: Which event triggers the transmission of Lawful Interception (LI) event information from the Home Subscriber Server (HSS) to Delivery Function 2 (DF2), according to lawful interception standards?
Option 1: PTC Session Initiation
Option 2: PTC Media Type Notification
Option 3: Service Registration
Option 4: HSS Subscriber Record Change
Explanation: The correct answer is 'HSS Subscriber Record Change' because this event is directly related to changes in subscriber data on the HSS, a critical trigger for lawful interception updates. The other options are either related to PTC sessions or unrelated to the HSS triggering events to DF2 as described.