It would be C. Rain. Water is evaporated from the earth into the sky to form clouds. Then it turns into rain that falls to the ground, and this process continues.
I hope this helped if you need a better explanation then ask, and I'll see if I can't provide you with one.
Answer: Earth reinforcing
Explanation: Earth reinforcing is a method of strengthening the soil/ground when constructing foundation by combining materials such as steel or concrete to the soil. It is especially useful for the construction of conventional retaining walls or mining structures.
Historically, steel nets were used on areas with soft clay, such as sea beds. Some materials used now include Geonets and geogrids.
It is in the desert of Asia it is the largest contigous sand desert in the world
hope this answer helped