The default PCM voice digitization rate is ____________.

The default PCM (Pulse Code Modulation) voice digitization rate is 64 Kbps. This rate is established based on the standard encoding for uncompressed audio signals in telecommunication systems, particularly for narrowband voice communications. PCM works by sampling an audio signal at a consistent rate and quantizing the sampled values into a series of digital values.

In this context, the PCM voice digitization involves a sample rate of 8,000 samples per second with 8 bits per sample, which results in the standard bitrate of 64 Kbps (8,000 samples/second * 8 bits/sample = 64,000 bits/second). This level of digitization ensures efficient transmission of voice signals in traditional telephony and many digital voice applications, providing clear audio quality while maintaining a reasonable level of data usage.

The other choices represent different bitrates that are commonly used in other contexts or types of audio encoding, but they do not align with the standard default set for PCM voice communication, reinforcing that 64 Kbps is indeed the correct and widely accepted answer.