Question: Which of the following Directory Files (DFs) under the USIM Application Dedicated File (ADF) level has a structure identical to the DFPHONEBOOK under DFTELECOM?
Option 1: DFGSM-ACCESS '5F3B'
Option 2: DFWLAN '5F40'
Option 3: DFPHONEBOOK '5F3A' (Application specific phonebook)
Option 4: DFProSe '5F90'
Explanation: The correct answer is Option 3 because, according to the specifications, the DFPHONEBOOK '5F3A' has the same structure as the DFPHONEBOOK under DFTELECOM, indicating it's application-specific and mirrors the telecom directory's phonebook structure for consistency across different applications.