Question

analyse causes of result into river pollution

Answer 1

Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). This form of environmental degradation occurs when pollutants are directly or indirectly discharged into waterbodies without adequate treatment to remove harmful compounds.

Answer 2

causes of river pollution are
bad drinking water
killing fishes or poisonous eating fishes
dying animals by dirty water