The correct answer to the following question will be "Safe and relatively low data and voice transmission".
Explanation:
Frequently, the word narrow band corresponds to ultra-high-frequency, S and L bands where the reasonable range is restricted compared to the bands of high-frequency.
It is desirable throughout the extremely-high-frequency, L-, including S-bands due to the beneficial propagation characteristics of the wavelengths.
Narrow band Satellite systems facilitate the efficient delivery of both wireless mobile networks at comparatively low bandwidths.
So, By the safe and low data transmission, it's the right answer.
The difference between analog and digital audio is that, analog refers to audio recorded using methods that replicate the original sound waves, and digital audio is recorded by taking samples of the original sound wave at a specified rate.