Explain how soil is formed. Define topsoil and subsoil.
a) Soil is formed through weathering of rocks. Topsoil is the upper layer rich in organic matter, while subsoil lies beneath it.
b) Soil is formed through volcanic eruptions. Topsoil is the layer with the most nutrients, while subsoil is rocky and barren.
c) Soil is formed through erosion of mountains. Topsoil is the deepest layer, while subsoil is compacted and nutrient-poor.
d) Soil is formed through glacier movement. Topsoil is the middle layer, while subsoil is the topmost layer.