Options are: I. Coal power II. energy III. friction IV. magic V. mechanical VI. Human power VII. Dog power VIII. Energy.
Given those answer options, answer the question: Fact 1: Pushing on the pedals of a bike cause that bike to move. Fact 2: Well, when riding a bike, human power is used to turn the pedals. Given the two facts above, what causes a bike to move?
A:
VI.