A. Distance from the Sun
B. Earth's axial tilt
C. Variations in solar output
D. Earth's rotation
Answer: Earth's axial tilt
A. Distance from the Sun
B. Earth's axial tilt
C. Variations in solar output
D. Earth's rotation
Answer: Earth's axial tilt
Additional Information: Seasons are primarily caused by the tilt of Earth's axis relative to its orbit around the Sun, which affects the intensity and duration of sunlight received in different regions.
Subjects: Physics