Description:

The correct answer is:

Earth's tilt relative to the Sun

Why?

Seasons occur primarily because:

Earth’s Axis is Tilted (~23.5°) – This means different parts of the planet receive varying sunlight intensity throughout the year.

Revolution Around the Sun – As Earth orbits, the Northern and Southern Hemispheres alternately tilt toward or away from the Sun, causing:

Summer (more direct sunlight, longer days).

Winter (less direct sunlight, shorter days).

Spring & Autumn (transitional periods).

What Doesn’t Cause Seasons?

Distance from the Sun: Earth’s orbit is nearly circular, so distance changes have minimal effect.

Ocean currents/Atmospheric pressure: These affect weather, not long-term seasonal cycles.

Fun Fact: When it’s summer in the Northern Hemisphere, it’s winter in the Southern Hemisphere—all thanks to the tilt! 🌍☀️❄️