Which of the following methods do rivers use to transport sediments?

Rivers primarily use the methods of suspension and traction to transport sediments. Suspension refers to the process where smaller particles, such as silt and clay, are carried within the water column. This allows these fine sediments to remain suspended due to the turbulence of the flowing water, making them effectively transported over long distances without settling to the riverbed.

Traction, on the other hand, involves the movement of larger sediments, such as stones and gravel, along the riverbed. In this process, heavier particles are rolled or slid along the bottom as the current pushes against them. Both suspension and traction are essential for the river to distribute sediments, contributing to the shaping of landscapes and ecosystems along its course.

The other options presented, such as evaporation and condensation, are processes related to the water cycle and do not pertain to sediment transport. Filtration and precipitation involve different aspects of water treatment and chemical processes, while conduction and convection relate to heat transfer mechanisms rather than sediment movement in rivers. Thus, those options do not accurately describe the ways in which rivers transport sediment.