Loose sediments are transformed into sedimentary rocks by the...

Lithification is the process by which loose, unconsolidated sediments are transformed into solid sedimentary rocks. This occurs through compaction, where the weight of overlying materials compresses the sediments, and cementation, where minerals precipitate from groundwater and bind the sediment particles together.

Weathering is the breakdown of rocks into smaller particles.

Mass wasting is the downward movement of rock and soil under gravity.

Solifluction is a specific type of mass wasting common in permafrost areas.

Answer: lithification