What role do solenoid valves play in hydraulic circuits?

Solenoid valves serve a crucial role in hydraulic circuits by enabling electronic control of fluid flow. These valves are operated by an electromagnetic coil that, when energized, moves a plunger to open or close the valve. This action allows for precise control over the movement and direction of hydraulic fluid within the system. By using solenoid valves, operators can automate processes, toggle flow paths, and quickly respond to changes in operational demands without the need for manual intervention.

In many hydraulic applications, the ability to control the fluid flow electronically enhances system efficiency and responsiveness. This integration of electrical and hydraulic components enables sophisticated control schemes, such as those found in automated machinery and robotics. Therefore, option B accurately captures the primary function of solenoid valves in hydraulic circuits.