B- Water Cycle will be the answer.
Answer:
We study about the sun because
The sun is a normal star. It is much closer to us than any other star, and by studying the sun, we can therefore learn more about other stars. The better we understand other stars, the more we know about the Milky Way. From there we know more about other galaxies and in the end we learn more about the universe.
Explanation:
How does the Sun help to protect life on Earth?
It radiates light and heat, or solar energy, which makes it possible for life to exist on Earth. Plants need sunlight to grow. Animals, including humans, need plants for food and the oxygen they produce. Without heat from the sun, Earth would freeze.
Alexander spread Greek technology and ideas through his empire where people talked and visited from all areas to see what had been done.
Because of Earth's axial tilt (obliquity), our planet orbits the Sun on a slant which means different areas of Earth point toward or away from the Sun at different times of the year. Around the June solstice, the North Pole is tilted toward the Sun and the Northern Hemisphere gets more of the Sun's direct rays.