The correct answer is: B. Pulse Code Modulation (PCM).
Pulse-code modulation (PCM) is a method used to represent an analog signal as a sequence of discrete values. The analog signal is sampled at regular intervals, and each sample is converted into a digital number. The digital numbers are then transmitted or stored.
PCM is the most common method of digital audio encoding. It is also used in many other applications, such as telephony, video recording, and data storage.
A digital signal generator is a device that produces a digital signal. It can be used to generate a variety of waveforms, such as sine waves, square waves, and sawtooth waves.
Pulse signal modulation is a general term for any modulation technique that uses pulses. It includes PCM, as well as other techniques such as pulse amplitude modulation (PAM) and pulse width modulation (PWM).
None of these is the correct answer.