Answer:
C. If farmers do not use soil conservation practices, the topsoil, which contains humus, will not be fertile to promote plant growth because of the loss of nutrients from the soil.
Step-by-step explanation:
The top soil is rich in humus and not weathered materials. It is not close to the bedrock. Rather, the topsoil is rich in organic matter and it is present as humus in the soil.
- If crop rotation is not being practiced, the soil's nutrients would be highly depleted without replenishing them back.
- With crop rotation the top soil can be made more fertile when it is left uncultivated for a period of time.
- Instead of heavily relying on a single piece of land, crops can rotated on a timed basis so that soils will have enough time to restore their nutrients.