Which Sequence Best Describes the Order of Soil Horizons in Well-Developed

question 6

Multiple Choice

Which sequence best describes the order of soil horizons in well-developed soil from top to bottom?

• A) Organic matter, mineral nutrients, clay, bedrock
• B) Organic matter, clay, mineral nutrients, detritus
• C) Mineral nutrients, organic matter, bedrock, clay
• D) Mineral nutrients, organic matter, clay, bedrock

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Definitions:

Oxygen-demanding Wastes

Organic wastes that reduce the amount of dissolved oxygen in water, often resulting from industrial or agricultural processes.

Activated Sludge

A process in wastewater treatment involving aerated microbial cultures that digest organic matter, reducing pollution before discharge into natural water bodies.

Biological Process

A process that occurs within living organisms, contributing to growth, reproduction, and other aspects of life.

Primary And Secondary

Refers to the first and second stages or levels in processes, industries, or education, often indicating a primary source or activity and its subsequent development or refinement.