You are presented with the question "Contact between rocks over long periods of time causes rocks to be what?" and the following answer choices: 
- coiled
 - homogenous
 - inactive
 - subrounded
 - dormant state
 - barrel-shaped
 - erosion
 - threatened

Now knowing that contact between rocks over long periods of time causes rocks to smooth and rocks on the streambed are subrounded and fairly smooth, choose the best answer.


 

    subrounded     