You are presented with the question "When a river floods, that river harms what?" and the following answer choices: 
- most organisms
 - Basic units of the plant body.
 - streams and volcanoes
 - mountains and lakes
 - farm and grazing lands
 - oceans and ponds
 - swamp vegetation
 - Plant growth is reduced

Now knowing that when a river floods , that river deposits soil in flood plains and soil erosion harms farm and grazing lands and increases flooding and desertification, choose the best answer.


 

     farm and grazing lands    