Question: In EVS AMR-WB IO mode, what is the primary purpose of adding zero bits to the payload?
Option 1: To enhance error correction capabilities for speech data transmission.
Option 2: To ensure the payload length is an integral number of octets (octet-aligned).
Option 3: To differentiate between EVS Primary and Secondary speech data.
Option 4: To increase the overall bitrate of the transmitted audio signal.
Explanation: Adding zero bits achieves octet-alignment, ensuring each payload can be neatly divided into octets. This simplifies parsing and interpretation of speech data at the receiver's end without affecting quality or introducing unnecessary complexity in error handling or signal differentiation.