A well developed soil have

Solution(By Examveda Team)

A developed soil or mature soil has three soil horizons whose physical, chemical, and biological characteristics differ from the layers above and beneath which help in nutrient supply and proper development of the plant.
The A horizon is the top layer of the mineral soil horizons, often referred to as "topsoil."
The B horizon is referred to as subsoil and consists of mineral layers which are significantly altered by pedogenesis.
The C horizon is below the solum horizons. The C horizon is enriched with carbonates carried below the solum by leaching.