The correct option is D Size of rocks
Wind, water, type of climate etc. play an important role in loosening up rocks and weathering them into smaller pieces. Soil formation due to weathering happens fastest in areas with hot and humid conditions. However, soil formation is slower in regions of cold regions.
Rocks, either big or small, are broken down in the same manner by the action of wind, rain or temperature. Therefore, the size of rocks doesn’t affect the weathering process.