The Earth revolving around the Sun causes the seasons to change on its axis, and seasons are caused because the earth's axis is tilted as the earth revolves around the sun. Given these facts, what causes seasons among the following options:
- moon
 - decreased differentiation
 - earth's revolving
 - the ocean
 - Physical weathering
 - colors of the spectrum
 - gravity
 - dry conditions


 

   earth's revolving      