Question: What is the primary purpose of the Frame Sequence Number Information Element (IE) in the context of UTRAN's Iu interface Radio Access Network Application Part (RANAP) signalling?
Option 1: To maintain continuity for numbering IuUP user data frames of PDU type 0 and 1 during RNSAP Relocation.
Option 2: To synchronize UE and RNC clocks for efficient handovers.
Option 3: To prioritize traffic flow for QoS enhancement in congested networks.
Option 4: To authenticate user data integrity across different RNCs in the UTRAN.
Explanation: The Frame Sequence Number IE ensures seamless continuity of IuUP user data frames (PDU types 0 and 1) during RNSAP Relocation, maintaining uninterrupted service as the user moves between different parts of the network.