Question: In a Cell Broadcast Service (CBS) scenario, what triggers the inclusion of a gNodeB ID in the Broadcast Empty Area List NG-RAN within a WRITE-REPLACE-WARNING-INDICATION-NG-RAN message sent by the Access and Mobility Management Function (AMF) to the Cell Broadcast Center Function (CBCF)?
Option 1: Receipt of a WRITE-REPLACE WARNING RESPONSE without a Broadcast Completed Area List from the NG-RAN node.
Option 2: Successful broadcast in all cells within the NG-RAN nodes.
Option 3: Failure to establish communication with the CBCF.
Option 4: Receipt of multiple responses from different NG-RAN nodes.
Explanation: This is correct because, according to the specifications, if the AMF receives a WRITE-REPLACE WARNING RESPONSE without a Broadcast Completed Area List from an NG-RAN node (identified by its gNodeB ID), it includes this gNodeB ID in the Broadcast Empty Area List NG-RAN within the indication message. This ensures the CBCF is informed about areas where the broadcast was not successfully completed.