Question

question 42
where is the highest concentration of organic matter in a soil profile?
it is equally distributed throughout.
at the top
near the base
in the middle

Explanation:

Organic matter in soil comes from decomposed plant and animal material. As these materials fall onto the soil surface and decompose, the highest concentration accumulates at the top layer (the O - horizon in soil profile terminology which is rich in organic matter). Deeper layers (like B or C horizons) have less organic matter as there is less input of fresh organic material from above and more leaching and mineral accumulation.

Answer:

At the top