Which of the following pressure types considers the pressure of the surrounding air to be zero?

The correct choice is gauge pressure, which is defined as the pressure measurement that disregards the pressure of the surrounding atmosphere. Instead of taking the ambient atmospheric pressure into account, gauge pressure measures how much pressure is above or below that atmospheric baseline. This means that if you have a gauge reading of, for instance, 30 psi, it signifies that the pressure inside the system is 30 psi greater than the atmospheric pressure.

Understanding how gauge pressure operates is essential in many applications where knowing the pressure relative to the environment is crucial, such as in tire pressures, hydraulic systems, and many industrial applications. The other pressure types are defined differently: absolute pressure measures total pressure including atmospheric pressure, atmospheric pressure reflects the pressure exerted by the weight of the atmosphere itself, and volumetric pressure doesn't apply as specifically in the context of fluid dynamics and pressure measurement.