Question: When using the `+CGSMS` command to select a service for MO SMS messages on a User Equipment (UE), what does setting `<service>` to `2` imply about the UE's preference for sending these messages?
Option 1: The UE will exclusively use Circuit Switched for all MO SMS messages.
Option 2: The UE prefers to use Packet Domain but will switch to Circuit Switched only if the UE is out of GPRS coverage.
Option 3: The UE prefers to use Packet Domain for MO SMS messages but will use Circuit Switched as a fallback if GPRS is not available.
Option 4: This setting is irrelevant in networks using E-UTRAN or NG-RAN.
Explanation: Setting `<service>` to `2` indicates the UE prefers to send MO SMS messages over Packet Domain (e.g., via GPRS), but will automatically fall back to Circuit Switched if a GPRS connection is not available, ensuring message delivery even in areas with limited packet-switched network coverage.