Which statement accurately describes a positive displacement pump?

A positive displacement pump operates by trapping a fixed amount of fluid in a chamber and then forcing it out of the chamber into the discharge pipe with each cycle or stroke. This method of operation ensures that a specific, finite volume of fluid is moved with every complete cycle, making the statement about discharging a finite quantity of water for each operating stroke accurate.

This characteristic distinguishes positive displacement pumps from other types, such as centrifugal pumps, which rely on kinetic energy and can handle varying flow rates depending on system pressure but do not operate on the principle of fixed volumes. The other statements do not accurately reflect the operational nature of positive displacement pumps. For instance, while some positive displacement pumps may not require priming, it is not a defining characteristic of all such pumps. Similarly, they do not typically operate continuously without stopping, as they function in strokes, nor are they specifically designed for high-speed applications, which is a characteristic more aligned with centrifugal pumps.