Question: In the TP-Validity Period of an SMS, what is the primary function of bit 7 in Octet 1 of the TP-VP functionality indicator?
Option 1: Indicates the start of a new validity period for a series of SMS messages.
Option 2: Signals that the TP-VP functionality indicator is extended to another octet (set to 1) or not (set to 0).
Option 3: Specifies the format for the Single Shot SM delivery attempt.
Option 4: Determines the rejection response for unsupported validity period formats.
Explanation: The correct answer accurately describes the function of bit 7 in Octet 1 of the TP-VP functionality indicator, indicating whether the TP-VP functionality is extended into another octet (set to 1) or not (set to 0), crucial for implementing and interpreting the TP-Validity Period correctly in SMS messaging.