Question: When is the Uplink data status IE included in the SERVICE REQUEST message?
Option 1: Only if the Allowed PDU session status IE is included in the SERVICE REQUEST message and there are no PDU sessions indicated for which user-plane resources can be re-established over 3GPP access.
Option 2: If the Uplink data status IE is included in the SERVICE REQUEST message, or if the Allowed PDU session status IE is included in the SERVICE REQUEST message and there is at least one PDU session indicated for which user-plane resources can be re-established over 3GPP access.
Option 3: Only if the Allowed PDU session status IE is not included in the SERVICE REQUEST message.
Option 4: If the Uplink data status IE is not included in the SERVICE REQUEST message, but the Allowed PDU session status IE is included.
Explanation: The correct answer is Option 2 because according to the specification, the Uplink data status IE shall be included if it is already present in the SERVICE REQUEST message or if the Allowed PDU session status IE is included and there is at least one PDU session for which user-plane resources can be re-established over 3GPP access.