Question: When does the Access and Mobility Management Function (AMF) include the 5GMM cause Information Element (IE)?
Option 1: When the Payload container IE contains an uplink payload which was not forwarded and the Payload container type IE is not set to Multiple payloads.
Option 2: When the Payload container IE contains a downlink payload which was successfully forwarded.
Option 3: When the Payload container type IE is set to Multiple payloads regardless of the forwarding status.
Option 4: When the AMF receives an uplink payload from the User Equipment (UE) during initial registration.
Explanation: The AMF includes the 5GMM cause IE in specific scenarios where it needs to convey information about the handling of uplink payloads. In this case, when the Payload container IE contains an uplink payload that was not forwarded and the Payload container type IE is not set to Multiple payloads, the AMF will include the 5GMM cause IE to provide additional context for the non-forwarded payload.