Question: Under what condition can a normally camped UE (User Equipment) initiate an Emergency Attach procedure, aside from being in a limited service state?
Option 1: When the UE has an existing non-emergency PDN (Packet Data Network) connection.
Option 2: During the GPRS PDP Context Activation procedure for emergency services.
Option 3: Under specific conditions, such as when the MM back-off timer is running.
Option 4: When the UE is transitioning from UTRAN to E-UTRAN access.
Explanation: A normally camped UE may initiate an Emergency Attach procedure under specific conditions, such as when the MM (Mobility Management) back-off timer is running. This scenario highlights an exception where a UE not in a limited service state can still perform an Emergency Attach, illustrating nuanced handling of emergency services in telecom networks.