Situation B (Growth and branching of roots in A and B horizons) is advantageous for absorption of water and minerals because the A and B horizons are richer in nutrients and water compared to the C horizon.
Explanation:
A and B horizons:
These horizons are typically composed of topsoil and subsoil, respectively, containing a higher concentration of organic matter, humus, and essential minerals like nitrogen, phosphorus, and potassium.
C horizon:
This horizon is primarily composed of weathered parent material with less organic content and nutrients.
Therefore, roots growing in the A and B horizons will have better access to water and nutrients, leading to more efficient absorption by the plant.