The process of mountain building is called Orogeny.
The answer is C, because it has a negative charge -1. All groups with charges called ions, unless they are organic compounds.
Earth's crust are pushing against each other miles below the Earth's surface, causing earthquakes, volcanoes and the movement of the continents. Approximately 30 plates are mapped out throughout the world. The plates consist of the Earth's crust and of the mantle, which is a thick layer of hot rock. Below that lies a sea of magma.
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