Answer:
it's the regolith
hope this helps you
C Horizon - Also called regolith: the layer beneath the B Horizon and above the R Horizon. It consists of slightly broken-up bedrock. Plant roots do not penetrate into this layer; very little organic material is found in this layer. R Horizon - The unweathered rock (bedrock) layer that is beneath all the other layers.
I think <span>500 m but i just think i dont know </span>
B) they have no charges and are inside an atom.*