Why sedimentation of suspended matter occurs?

When soil is eroded from the water 

The correct answer is option 3. When soil is eroded from the water

Sedimentation of suspended matter occurs when soil particles are eroded from the land and carried by water. The suspended particles, such as clay, silt, and sand, settle down and accumulate in bodies of water due to the gravitational pull, leading to the process of sedimentation. This can affect water quality and aquatic ecosystems, leading to issues such as decreased light penetration, habitat degradation, and altered nutrient levels.