Fact 1: The moon revolving around the Earth causes the phases of the moon.

Fact 2: Phases of the Moon are caused by differing amounts of light reflected from the Earth.

Given the two facts above, answer the question "What causes differing light to reflect off of the moon?" with the following options: 
- depress neuronal excitability
 - energy of moving objects
 - The revolution around earth
 - our nearest star
 - a hemisphere is tilted away from the sun
 - focusing a lens
 - flow of electrons
 - that material's properties


 

   The revolution around earth      