Earth Science Practice Exam 2025 – Comprehensive Study Resource

The formation of sedimentary rocks is primarily a result of weathering and erosion of pre-existing rocks, which breaks down rocks into smaller particles called sediments. This process involves the physical and chemical breakdown of rocks due to weathering from atmospheric conditions, such as temperature changes, wind, and water. These sediments can then be transported by erosion via water, wind, or ice to different locations.

Once the sediments are deposited, they undergo further processes, such as compaction and cementation, which cause them to stick together and eventually solidify into sedimentary rock. This is distinct from other processes like melting, which pertains to the formation of igneous rocks when rocks are transformed into magma, or solidification, which does not apply as directly to the processes involved in sedimentary rock formation. Nucleation similarly refers to the initial stage of crystal formation and is not relevant to the sedimentary rock process. Overall, weathering and erosion are fundamental in creating the materials that lead to sedimentary rock formation, making this the correct answer.