How do hydraulic systems operate based on Pascal's Principle?

Hydraulic systems operate by leveraging Pascal's Principle, which states that in a confined fluid at rest, any change in pressure applied at any point in the fluid is transmitted undiminished throughout the fluid in all directions. This principle allows hydraulic systems to efficiently transmit force by using incompressible fluids, such as oil or water.

When force is applied to the fluid in one part of the hydraulic system, that force creates a pressure change that is transmitted equally throughout the fluid. This capability allows the system to amplify force, enabling heavy loads to be moved with a relatively small input force. Therefore, the crux of hydraulic systems lies in their ability to utilize incompressible fluids to achieve equal transmission of force in every direction, making option C the correct choice.

Other methods of operation, such as employing compressible gases, magnetic forces, or gravity, do not align with the fundamental workings of hydraulic systems as dictated by Pascal's Principle.