Question: In a Single USSD Message for (U)SIM Toolkit applications, how is the Command Packet Identifier (CPI) value specified within the generic Command Packet structure?
Option 1: CPI value is dynamically allocated based on the application
Option 2: CPI value is set to '00' for all USSD-related commands
Option 3: CPI value is determined by the User Equipment (UE)
Option 4: CPI value is fixed as '03' for USSD String Command Packets
Explanation: The correct answer reflects the specification that within the context of a Single USSD Message for (U)SIM Toolkit applications, the Command Packet Identifier (CPI) is standardized to a fixed value. This ensures consistency and proper routing/processing of USSD commands across different (U)SIM and network infrastructures.