This question is based on the following poem:    Seasons are celebrations.    A year's a Ferris wheel.    Both honor our world's habit    of spinning 'round a star. Which one of the following sentences best expresses the main idea of this poem? A. There are four seasons in a year. B. Seasons are celebrations, while a year on Earth is a habit. C. The world has a habit of spinning around. D. Seasons and Ferris wheels are like Earth's journey around the sun.