Pneumonia may be caused by an infection or injury of the lungs, and mammals breathe air with lungs. Given these facts, what may be caused by an infection or injury of the organs used to breathe air among the following options:
- Toxicity
 - smoking
 - fertilization
 - pneumonia
 - a broken leg
 - oxygenation
 - Dehydration
 - the skin


 

    pneumonia     