Question: In the EVS VBR Encoder, what is the primary goal of adjusting the proportion of low bit-rate (2.8 kbps) and high bit-rate (7.2, 8 kbps) frames in terms of target outcome?
Option 1: To minimize latency in voice transmission
Option 2: To maximize the number of concurrent calls on a network
Option 3: To prioritize voice quality over data integrity
Option 4: To achieve an average bit-rate of approximately 5.9 kbps for optimal voice quality
Explanation: The correct answer is Option 4 because the question directly relates to the mechanism described for the VBR (Variable Bit Rate) mode in the EVS (Enhanced Voice Services) encoder, which involves adjusting the mix of low and high bit-rate frames to target an average bit-rate that balances efficiency with voice quality.