Question: In the context of UTRAN's Iu interface, what is the primary purpose of the MBMS UE Linking Function when a UE has an existing dedicated Iu-PS signalling connection?
Option 1: To establish a new dedicated Iu-PS signalling connection for MBMS services.
Option 2: To manage the QoS (Quality of Service) parameters for individual UEs on the Iu interface.
Option 3: To provide the RNC with updates on which MBMS services a UE has joined or left.
Option 4: To handle the authentication process for UEs accessing MBMS services.
Explanation: The correct answer reflects the function's role in updating the RNC about changes in a UE's MBMS service subscription status (joined or left) when the UE already has a dedicated Iu-PS signalling connection established, crucial for efficient resource allocation and service delivery.