Question: Under what condition(s) will a UE (User Equipment) inform its upper layers about the possible failure to deliver `ULInformationTransfer` messages, excluding cases where the messages only contain `dedicatedInfoF1c`?
Option 1: When AS (Access Stratum) security is not initiated and a radio link failure occurs before delivery confirmation, or during PDCP re-establishment/release/addition on an affected SRB (Signaling Radio Bearer).
Option 2: Only when there's a handover failure between different eNodeBs (evolved Node Bs) without any impact on AS security initialization.
Option 3: If the UE transitions from RRC (Radio Resource Control) Connected to Idle state without completing the message transmission.
Option 4: When the MME (Mobility Management Entity) rejects an S1 Setup request, prompting a re-evaluation of pending ULInformationTransfer messages.
Explanation: This is correct because, as specified, the UE informs upper layers about potential delivery failures under two conditions: (1) if AS security hasn't started and a radio link failure happens before confirmation of successful delivery, or (2) during PDCP re-establishment/release/addition on an SRB where message delivery wasn't confirmed. This aligns with ensuring the reliability of critical signaling exchanges in telecom networks, particularly under conditions that might compromise message integrity or confidentiality.