What defines the layers that comprise bedrock in relation to wastewater systems?

The correct choice emphasizes the relationship between bedrock and the soil horizons directly above it. In the context of wastewater systems, understanding the layers that comprise bedrock is critical because it informs how wastewater will interact with underlying materials.

Choice C suggests that bedrock layers should be characterized by interlayered soil horizons that exist above them. This is significant because these soil horizons can affect drainage, filtration, and the potential for contamination. Soil horizons serve as an essential buffer, providing a transition that can impact how water moves through the ground and affects the integrity of wastewater systems.

When bedrock is examined, its relationship to the soil horizons above helps in assessing the overall health of the wastewater system. Well-defined soil horizons can indicate organic material presence, compaction, drainage capabilities, and overall suitability for wastewater absorption, which is fundamental for ensuring compliance with environmental standards and protecting groundwater.

The other choices do not accurately encapsulate the significance of how bedrock and its layers interact with wastewater systems, nor do they address the requirement of understanding the soil context when assessing bedrock layers for wastewater management purposes.