Question: In which MM IDLE substate can a mobile station initiate only emergency services and test/reconfiguration calls, with valid subscriber data available and update status U4?
Option 1: NORMAL SERVICE (19.1)
Option 2: LIMITED SERVICE (19.3)
Option 3: NO IMSI (19.4)
Option 4: eCALL INACTIVE (19.11)
Explanation: In the MM IDLE substate "eCALL INACTIVE" (19.11), a mobile station can initiate only emergency services and test/reconfiguration calls, with valid subscriber data available and update status U4. This state is applicable only to an eCall only mobile station, as determined by information configured in USIM.