the days in a year the hours in a day the changes in the atmosphere of Earth the position of the constellations in space
I gave my students this multiple choice question: The motion of Earth is responsible for several celestial events. Which of the following events is caused by Earth revolving around the sun?

Only one answer is correct among these 4 choices:
- the days in a year
- the hours in a day
- the changes in the atmosphere of Earth
- the position of the constellations in space

Could you tell me which one is correct?

the days in a year