Why do people say that the sun set when it doesn’t

The sun stays in its position at the center of our solar system. it doesn't rise and set. But is appears to rise and set because  of the earths rotation on its axis. As the earth rotates toward the east it looks like the sun is moving west

it's c. (to reduce the greenhouse effect/carbon gasses)

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint