You are presented with the question "what dissolves oxygen better when running than standing?" and the following answer choices: 
- H2O
 - NaCl
 - pH
 - CO2
 - CO 2
 - O2
 - O3
 - H20

Now knowing that running water is better able to dissolve oxygen and nutrients than standing water and water is made up of H2O molecules, choose the best answer.


 

 H2O        