Erosion is best defined as . A. the process of rock and soil being carried away by natural forces B. the process of rock being broken down by chemical changes C. the process of rock being weakened slowly over time D. the process of rock being broken down by extreme temperatures

1. crust 1 the metallic layer at the earth's center 2. inner core 3 the firm layer between the crust and the asthenosphere 3. lower mantle 2 the layer surrounding the inner core 4. asthenosphere 4 the semi-solid layer between the top layer and the upper mantle 5. upper mantle 5 the layer between the asthenosphere and lower mantle 6. top layer 6 the earth's outermost layer 7. outer core 7 the hottest part of the mantle