Which component forms part of the braking system?

The component that forms part of the braking system is the speed sensor. Speed sensors play a critical role in the overall functionality of a vehicle's braking system, particularly in modern systems like Anti-lock Braking Systems (ABS). These sensors monitor the rotational speed of the wheels, providing essential data to the vehicle’s electronic control unit (ECU). This information helps the ECU to optimize brake application and prevent wheel lock-up during hard braking situations, thereby enhancing vehicle control and safety.

In contrast, the other components listed do not belong to the braking system. The clutch disc and flywheel are integral parts of the vehicle's drivetrain, responsible for engaging and disengaging the engine from the transmission, while the strut is part of the suspension system, aiding in vehicle stability and ride comfort. Understanding the specific roles of these components helps clarify the distinction between the braking system and other systems within a vehicle.