You are presented with the question "what pollutes the environment?" and the following answer choices: 
- bacteria
 - airplanes
 - deforestation
 - moon
 - sun
 - cells
 - Smoking
 - flooding

Now knowing that aairplane is used for moving people across bodies of water and airplanes are responsible for air, noise, and water pollution, choose the best answer.


 

  airplanes       