Question: What is the indication type set by a Relay UE when it initiates transmission of the NotificationMessageSidelink message due to Uu RLF?
Option 1: relayUE-Uu-RLF
Option 2: relayUE-HO
Option 3: relayUE-CellReselection
Option 4: relayUE-Uu-RRC-Failure
Explanation: According to the protocol specification, when a Relay UE initiates transmission of the NotificationMessageSidelink message due to Uu RLF (Radio Link Failure), it sets the indication type as "relayUE-Uu-RLF". This is specific to the scenario where the UE is acting as a U2N Relay UE and experiences a radio link failure on the Uu interface.