You are presented with the question "what makes a river wider?" and the following answer choices: 
- rainfall
 - salinity
 - arteries
 - flow of electrons
 - Water expanding
 - Physical weathering
 - a hydraulic system
 - clearing land

Now knowing that erosion causes a river to become deeper and wider and clearing of land can lead to erosion of soil into the river, choose the best answer.


 

        clearing land 