What is the primary purpose of the hydrostatic test?

The primary purpose of a hydrostatic test is to determine if pump and piping systems can withstand operational pressures. This process involves filling the system with water and applying pressure to ensure that there are no leaks and that the materials can handle the stress they will face during normal operation. By conducting this test, operators can ensure the integrity and safety of the water supply system, which is critical for preventing failures during actual use.

Other options focus on different aspects of operational performance. Checking engine performance and evaluating fuel efficiency relate more to the vehicle's or equipment's functionality rather than the structure of the water supply system itself. Assessing pump efficiency involves measuring how well the pump operates, but it does not specifically address the capacity of the pump and piping to endure pressure without failure. Thus, option C is the most accurate choice regarding the purpose of a hydrostatic test.