What component transfers power from the engine to a manual transmission?

The clutch disc plays a critical role in transferring power from the engine to the manual transmission. In a manual transmission system, the clutch acts as a coupling device that allows the driver to connect or disconnect the engine's rotational force to the transmission. When the clutch pedal is pressed, the clutch disc disengages from the flywheel, interrupting the transfer of power, which enables the driver to change gears smoothly without grinding the gears.

Once the pedal is released, the clutch disc re-engages with the flywheel, allowing the engine's power to be transmitted through the transmission to the drive train, ultimately propelling the vehicle. The effective operation of the clutch disc is essential, as it allows for controlled power transfer and facilitates gear shifts, contributing significantly to the overall performance and drivability of the vehicle.

Other components listed serve different functions; for instance, a torque converter is used in automatic transmissions to manage power transfer differently, and a drive shaft is responsible for transferring power from the transmission to the wheels, not directly from the engine to the transmission. Thus, the clutch disc is the correct answer as it specifically manages the direct connection and disconnection of engine power in manual transmissions.