Concept:The soil profile is made up of different layers called horizons, each with a letter name.
Explanation:The B-horizon is the layer found just below the topsoil (A-horizon).
It is commonly known as the sub-soil.
This layer collects minerals and clay that are washed down by water moving through the soil.
The parent material and bedrock are found in deeper horizons, not in the B-horizon.
Answer:The B-Horizon of the soil profile is also called the sub-soil.
Therefore, the correct option is B. Sub-soil.