Question: What is the primary purpose of storing a value in the EFPUID (Previous Unique Identifier) file on a Universal Subscriber Identity Module (USIM)?
Option 1: To quickly generate a new unique identifier for phone book synchronization, which is then stored in the EFUID.
Option 2: To store multiple e-mail addresses linked to a single phone book entry.
Option 3: To provide a backup for the currently used unique identifier in case of data loss.
Option 4: To enhance security by periodically changing the unique identifier for phone book entries.
Explanation: The correct answer is Option 1 because the purpose of EFPUID is to allow the terminal to quickly generate a new UID (stored in EFUID) for synchronization purposes, specifically related to phone book entries, ensuring efficient management and updating of unique identifiers for phone book synchronization.