Question: What is a key characteristic of the Service Dialling Numbers feature in relation to updating the stored numbers?
Option 1: The user has full control over updating the numbers through a standardized MMI.
Option 2: Updating the numbers is under the control of the mobile device manufacturer.
Option 3: Access for updating the numbers is strictly controlled by the network operator/service provider.
Option 4: Updates can only be made by physically replacing the SIM/USIM.
Explanation: This correct answer reflects a crucial aspect of the Service Dialling Numbers feature, emphasizing the control that network operators/service providers have over updating these numbers. This ensures that only authorized changes are made to the service-related dialing numbers stored on the SIM/USIM, maintaining the integrity and security of the services offered. The incorrect options (1, 2, and 4) misrepresent the control dynamics, user interface specifications, or the process for updating these numbers as per the telecom domain’s understanding of such features.