Fact 1: The Earth being tilted on its rotating axis causes seasons.

Fact 2: Spring, summer, autumn, and winter are the seasons of the year.

Given the two facts above, answer the question "What causes spring, summer, autumn, and winter?" with the following options: 
- meteor showers
 - heat production
 - the sun's energy
 - Generating heat
 - Earth tilted on rotating axis
 - Something with a head, thorax, and abdomen
 - Earth vibrating
 - lunar cycle


 

     Earth tilted on rotating axis    