Question: In an SMS-DELIVER or SMS-STATUS-REPORT, what does a '1' value in the TP-More-Messages-to-Send field indicate about messages waiting for the Mobile Station (MS) at the Short Message Service Center (SC)?
Option 1: Additional SMS-messages or status reports are buffered for delivery to the MS.
Option 2: No additional SMS-messages or status reports are waiting for the MS in this SC.
Option 3: The MS has undelivered MMS messages pending at the SC.
Option 4: The SC is experiencing a delay in processing incoming SMS-messages.
Explanation: A '1' value in the TP-More-Messages-to-Send field signifies that no more messages (SMS-messages or status reports) are waiting for the Mobile Station (MS) at the Short Message Service Center (SC), ensuring efficient management of message delivery expectations.