Fact 1: Pushing on the pedals of a bike cause that bike to move.

Fact 2: Speed is controlled by pedalling and by pushing back on the moving pedals.

Given the two facts above, answer the question "What is controlled by pushing on bike pedals?" with the following options: 
- motion
 - weight
 - pressure
 - health
 - cycles
 - driving
 - Energy.
 - speed


 

        speed 