Answer:
C
Explanation:
Because the hot magma flow in the convection currents and these currents move the tectonic plates and make up the Earths crust.
Subsoil: This layer has normally less organic matter than the A horizon, so its colour is mainly derived from iron oxides. Iron oxides and clay minerals accumulate as a result of weathering. In a soil, where substances move down from the topsoil, this is the layer, where they accumulate.
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