Q. What is the topmost horizon of the soil called?
Answer: A - Horizon
Notes: The different layers of the soil are arranged in a vertical manner, which is known as the soil profile. The topmost horizon is usually dark in colour. It contains humus, which is decomposed organic matter, and various minerals. This makes it the best layer for the growth and survival of plants. It is generally porous and can retain moisture to a good extent. This is called the topsoil or the A-horizon.