Which component transforms pedal action into pressurized brake fluid in a hydraulic brake system?

• A. Brake Booster
• B. Proportioning Valve
• C. Master Cylinder
• D. Caliper Piston

Answer: (C)

The master cylinder is where pedal action becomes hydraulic pressure. When you push the brake pedal, a pushrod moves piston(s) inside the master cylinder, forcing brake fluid into the closed hydraulic circuits and creating pressure. That pressure is sent through the brake lines to the calipers or wheel cylinders, which then clamp the pads onto the rotors to slow or stop the vehicle. The brake booster mainly reduces the effort needed to push the pedal by providing vacuum assist, but it doesn’t generate pressure. The proportioning valve only adjusts how pressure is distributed between circuits, and the caliper piston uses the hydraulic pressure to apply the brakes but doesn’t create it.