You are presented with the question "Deepening rivers cause" and the following answer choices: 
- relocation
 - the loss of topsoil
 - Plant growth is reduced
 - to move people
 - Physical weathering
 - forest is destroyed
 - Water expanding
 - water conservation

Now knowing that erosion causes a river to become deeper and wider and fertile topsoil is then lost in erosion, choose the best answer.


 

  the loss of topsoil       