Which of the following parts of a tool would require the tool to have a guarding device?

Belts, gears, and pulleys require a guarding device.  

Guarding machines act as a safety feature and consist of a shield covering dangerous areas of the machine to prevent contact with the body parts from chips or sparks from exiting the machine. Belts, gears, and pulleys can cause accidents so they require to be guarded at all times

answer; i do believe its (faster);