Which of the following is defined as weathering caused by the activities of living organisms?

Biological weathering refers to the process of weathering that occurs due to the actions of living organisms. This can involve plants, animals, fungi, and microorganisms contributing to the breakdown of rocks and minerals. For instance, plant roots can grow into cracks in rocks, exerting pressure as they expand, and can also produce organic acids that break down minerals in the rocks. Similarly, burrowing animals can disturb the soil and expose rock surfaces to weathering processes.

This form of weathering is distinct from other types because it emphasizes the specific role of organisms in altering and breaking down geological materials. While physical weathering involves mechanical processes such as freeze-thaw cycles, and chemical weathering focuses on chemical reactions (like oxidation or hydrolysis), biological weathering uniquely highlights the influence of the biosphere on rock and soil formation and alteration.