You are presented with the question "Rivers easily dissolve nutrients and:" and the following answer choices: 
- bacteria
 - chemicals
 - oxygen
 - sodium
 - vitamin C
 - glucose
 - a solute
 - a hazard

Now knowing that running water is better able to dissolve oxygen and nutrients than standing water and large, warm rivers hold populations but few occur in cold running water, choose the best answer.


 

   oxygen      