Fact 1: Most canyons are formed by flowing rivers through erosion over long periods of time.

Fact 2: Erosion is the work of wind, water, and time.

Given the two facts above, answer the question "Water and time can work together to create what?" with the following options: 
- a wave
 - canyon
 - matter
 - heat
 - soils
 - mercury
 - iron
 - desert


 

  canyon       