What type of operating mechanism utilizes gas to function?

The correct answer is pneumatic because this term specifically refers to systems that operate using gas or air pressure to perform work. In pneumatic mechanisms, compressed air is used to transmit power, allowing for the movement and control of tools, actuators, and machines. This principle is employed in various applications, such as in pneumatic drills, cylinders, and automotive systems, which rely on the expansion and pressure of gas to generate motion.

The other types of mechanisms have different operating principles: hydraulic systems use liquids (typically oil) under pressure; magnetic systems utilize magnetic fields to exert force or move objects; and mechanical systems encompass a broader category, including various devices that may or may not use gas or fluids for operation. Understanding these distinctions clarifies why pneumatic is the most appropriate choice for this question.