Question: When a Universal Subscriber Identity Module (USIM) application is present on a Universal Integrated Circuit Card (UICC) in a 3GPP Mobile Equipment (ME), how does the ME utilize the USIM and SIM applications across different radio access technologies?
Option 1: The ME uses both USIM for 3G/4G/5G and SIM for 2G, depending on the radio access technology.
Option 2: The ME uses the SIM application for all radio access technologies if it is present alongside the USIM.
Option 3: The choice between USIM and SIM depends on user settings in the ME, regardless of the radio access technology.
Option 4: The ME exclusively uses the USIM application for all radio access technologies, ignoring any existing SIM application.
Explanation: If a USIM application is present on the UICC, a 3GPP Mobile Equipment (ME) will only utilize the USIM application, disregarding the radio access technology in use and ignoring any possibly existing SIM application, ensuring consistency with the more advanced capabilities typically offered by the USIM across all supported network technologies.