Which factor does not contribute to seasonal changes?

• A. Earth's tilt
• B. Orbit around the Sun
• C. The Moon's gravity
• D. The concentration of sunlight hitting Earth

Answer: (C)

Seasonal changes come from how Earth’s axis is tilted relative to its orbit around the Sun. That tilt changes the angle at which sunlight hits different parts of Earth and how long each hemisphere is exposed to daylight over the year, altering energy per unit area and temperature. The orbit around the Sun can tweak the amount of solar energy a bit because Earth is not a perfect circle, but this is a secondary effect and mainly modulates distance rather than causing the seasons themselves. The Moon’s gravity, however, doesn’t affect the tilt or how sunlight is distributed across the globe; it influences tides and lunar motion, not the seasonal pattern. So the Moon’s gravity is the factor that does not contribute to seasonal changes.