Answer: B soil is also called the SUBSOIL.
Soil horizon consists of layers of soil that differ physically. It contains 3 or 4 layers or horizon such as O horizon, A horizon, B horizon, C horizon and R horizon. B horizon is also referred as subsoil. It is yellowish to brown in color. It consists of mineral layers such as silicate clay, iron, aluminium, gypsum, silica, humus, etc. The roots of a plant penetrates through the subsoil.