Question: In a USIM's EFSMSS (SMS status) file, what does the setting of `b1=0` for the 'Memory Capacity Exceeded' Notification Flag indicate about the UE's memory capacity?
Option 1: The UE has sufficient memory capacity to receive new SMS messages.
Option 2: The UE's memory capacity is exceeded, and it cannot receive new SMS messages until space is freed.
Option 3: The UE is experiencing a temporary issue with message processing, pending a network update.
Option 4: The flag setting is irrelevant to the UE's ability to receive or store SMS messages.
Explanation: According to specifications, when `b1=0` for the 'Memory Capacity Exceeded' Notification Flag in the EFSMSS file, it signifies that the memory capacity is exceeded. This means the UE cannot accommodate new SMS messages until more storage space becomes available, facilitating managed message delivery due to depleted memory.