You are presented with the question "The work of what causes a river to become deeper and wider?" and the following answer choices: 
- looseness of dirt or compost
 - just time
 - Veins and arteries.
 - just wind
 - Physical weathering
 - The area was once underwater
 - just water
 - wind, water, and time

Now knowing that erosion causes a river to become deeper and wider and erosion is the work of wind, water, and time, choose the best answer.


 

        wind, water, and time 