Streams and moving water are the major agents of which geological process?

• A. Deposition
• B. Erosion
• C. Weathering
• D. Frost Wedging

Answer: (B)

Streams and moving water are powerful forces that wear away rock and soil and carry the resulting sediment to new locations. This action is erosion—the process of removing and transporting material by natural forces. While water also contributes to weathering—the breakdown of rocks in place—erosion is the main way streams reshape landscapes by carving channels, widening valleys, and moving material downstream. Deposition occurs after erosion when the sediment settles out, so it is a consequence of erosion rather than the primary process driven by moving water. Frost wedging is a weathering mechanism caused by freeze-thaw cycling in cracks, not the main erosion process.