What is the simple meaning of soil erosion?

Correct answer: Removal of topsoil

Soil erosion is the wearing away and movement of the upper, fertile layer of soil by agents such as running water, wind, or sometimes human activity. The topsoil contains organic matter and nutrients needed by many crops, so its removal can reduce agricultural productivity and damage land. Therefore, option D is correct because it gives the simple meaning of soil erosion. Adding manure improves soil nutrients, planting trees can help prevent erosion, and saving water is a conservation practice but not the definition of erosion. Vegetation, grass cover, contour farming, terracing, and careful water management can reduce the force of wind and runoff. The governing green-skills concept is protecting soil as a natural resource for sustainable farming and ecosystems.