Question: When should the S-NSSAI IE be included in the message by the SMF?
Option 1: When the AMF sends an S-NSSAI with the PDU SESSION ESTABLISHMENT REQUEST message, regardless of the PDU session type.
Option 2: When the UE is registered for onboarding services in SNPN and the PDU session is a non-emergency PDU session.
Option 3: When the SMF receives an S-NSSAI from the AMF, but only if the PDU session is an emergency PDU session.
Option 4: When the SMF received from the AMF an S-NSSAI together with the PDU SESSION ESTABLISHMENT REQUEST message, the PDU session is a non-emergency PDU session and the UE is not registered for onboarding services in SNPN.
Explanation: The correct answer is Option 4 because it accurately describes the conditions under which the S-NSSAI IE should be included in the message by the SMF, as specified in the text. This includes receiving an S-NSSAI from the AMF with the PDU SESSION ESTABLISHMENT REQUEST message, the PDU session being non-emergency, and the UE not being registered for onboarding services in SNPN.