You are presented with the question "What keeps smoke out of the respiratory system?" and the following answer choices: 
- Cooking
 - Masks
 - Glasses
 - skin
 - Gloves
 - Hats
 - Urea
 - oxygen

Now knowing that abreathing mask is used for keeping harmful particles from entering the respiratory system and all smoke is harmful to the respiratory system, choose the best answer.


 

  Masks       