Which of the following instruments generates the pulse of sound?

The pulser is the component of a sonography system responsible for generating electrical pulses that are then converted into sound waves by the transducer. This generation of pulses is essential because it determines the timing and frequency of the ultrasound waves emitted into the body. The pulser controls parameters such as the pulse repetition frequency and the overall strength of the sound waves, which can impact image quality and penetration.

In contrast, the amplifier plays a role after the sound waves have been transmitted and received; it amplifies the returning signals to improve the quality of the images. The transducer, while critical in converting electrical signals into sound waves and vice versa, does not generate the pulse itself—its function is to facilitate this conversion. The beam former is involved in directing the sound waves produced by the transducer in a specific manner but does not generate the initial pulse.

Therefore, the pulser is integral to the creation of the initial sound pulse, making it the correct answer in this context.