Final answer:
The layer of soil that is made up of solid rock is known as the bedrock. This layer lies beneath the subsoil, topsoil, and organic layer.
Step-by-step explanation:
The layer of soil made up of solid rock is referred to as the bedrock. The soil layers above the bedrock include the subsoil, topsoil, and organic layer. Organic material of the soil is made up of humus, which provides the soil with water and minerals while the inorganic material of soil is made up of rock slowly broken down into smaller particles, leading to varying layers of soil with differing properties. The bedrock lies beneath these layers and is formed from solid rock, providing a base for the overlying soil structure.
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