Question: What action does the SMS-IWMSC take if the HLR returns error information during the processing of a "forwardShortMessage" request?
Option 1: Establish a link with the addressed SC to attempt delivery
Option 2: Inspect the IMSI parameter to determine the next course of action
Option 3: Return the appropriate error information to the MSC or SGSN in a failure report
Option 4: Transfer the short message TPDU to the SC with an error flag
Explanation: When the HLR returns error information during the "forwardShortMessage" process, the SMS-IWMSC's primary responsibility is to communicate this failure back to the originating node (MSC or SGSN). This ensures that the sender is notified of the delivery failure in a timely manner. Returning error information in a failure report is a critical step in managing message delivery outcomes and maintaining network efficiency.