Which of the following parameters affects the width of the ultrasound sector?

The width of the ultrasound sector is primarily influenced by the frequency of the ultrasound beam. When the frequency is adjusted, it can determine how the ultrasound waves are produced and focused, which in turn affects the sector's width. Higher frequencies typically produce narrower beams, allowing for tighter focusing within the ultrasound images, whereas lower frequencies may create wider beams, resulting in a broader sector width.

Understanding the role of frequency is crucial because it affects the spatial resolution and penetration of the ultrasound waves; a narrower sector can provide more detailed images of a smaller area, while a wider sector can cover a larger anatomy but may sacrifice some image clarity and depth resolution.

Other factors listed, such as gain, dynamic range, and overall intensity, do not influence the width of the ultrasound sector directly. Gain adjusts the amplification of the received signal, dynamic range pertains to the range of echo amplitudes that can be processed, and overall intensity refers to the power of the ultrasound waves. However, these parameters do not change the geometric configuration of the ultrasound sector.