What component applies pressure to the master cylinder in a brake system?

In a brake system, the master cylinder is a crucial component that plays a vital role in creating hydraulic pressure, which is essential for activating the brakes. The brake pedal is directly connected to the master cylinder, and when the driver presses the brake pedal, it forces a plunger inside the master cylinder to move. This movement compresses the brake fluid contained within the master cylinder, generating the hydraulic pressure necessary to engage the brakes at each wheel.

Understanding the function of the brake pedal helps clarify its importance in initiating the braking process. The pressure generated by the master cylinder is then transmitted through the brake lines to the brake components at each wheel, allowing the vehicle to slow down or come to a stop.

The other options, while related to automotive systems, do not have a role in applying pressure to the master cylinder. Brake lines are used to transfer the hydraulic fluid but do not create pressure themselves. The torque converter is part of the transmission system, and the clutch is associated with manual transmission vehicles, functioning to engage and disengage the engine from the transmission.