What is another word for C horizon?
Pronunciation: [sˈiː həɹˈa͡ɪzən] (IPA) 
The C horizon, also called the parent material or bedrock, is the layer of soil that lies beneath the B horizon. It is made up of partially weathered rocks, gravel, and sand. Synonyms for the C horizon include the regolith and the substratum. The regolith refers to the layer of unconsolidated and loose materials that cover the bedrock. In contrast, the substratum refers to the underlying layer that is more solid and unweathered. Other related terms include the saprolite, which is the soft and clay-like soil that forms from the weathering of rocks, and the lithosphere, which is the outermost layer of the Earth's crust that includes both the bedrock and soil layers.
