Final answer:
The term 'Increased depth of view' does not belong with the others because it is a result of wave properties rather than a direct descriptor like the rest.
Step-by-step explanation:
The term that does not belong with the others is A. Increased depth of view. Options B, C, and D are all related to the properties of ultrasound waves used in medical imaging. Decreased duty factor (B), increased pulse repetition period (C), and decreased spatial pulse length (D) are all terms that influence the quality and safety of the ultrasound procedure. Meanwhile, increased depth of view is a result of manipulating these settings but is not a direct descriptor of the ultrasound wave properties themselves. When considering the relationship between the period and frequency of a wave, when the period of a wave increases, its frequency decreases (A).