You are presented with the question "pushing on the pedals of a bike cause what?" and the following answer choices: 
- electromagnetic energy
 - Pollution
 - friction reduction
 - kinetic energy
 - decreases its bodily water
 - mechanical
 - get started
 - Heart rate

Now knowing that pushing on the pedals of a bike cause that bike to move and wheels reduce friction with the floor to help cars move, choose the best answer.


 

   friction reduction      