Here's why:
* Revolution: The Earth orbits the Sun in an elliptical path. One complete revolution around the Sun takes approximately 365.25 days.
* Year: This period of revolution is what defines a year.
* Seasons: The Earth's tilted axis causes different parts of the planet to receive varying amounts of sunlight throughout the year, resulting in the seasons.
Therefore, the completion of one Earth revolution around the Sun marks the passage of one year.
