Question: In a scenario where a remote User Equipment (UE) loses cellular network coverage, what is the primary function of the Proximity Services (ProSe) UE-to-Network Relay for Mission Critical (MC) services?
Option 1: To establish a new cellular connection for the remote UE
Option 2: To provide a layer 2 tunnel for direct device-to-device communication
Option 3: To offer a purely layer 3 IP data routing service for accessing MC services
Option 4: To handle only voice calls for emergency services on the remote UE
Explanation: The ProSe UE-to-network relay provides a purely layer 3 IP data routing service, enabling the remote UE to access MC services through the relay without a new cellular connection or relying on direct device-to-device communication at layer 2 for this purpose.