You are presented with the question "what has a negative impact on the respiratory system?" and the following answer choices: 
- harmful substances
 - water-damaged carpets
 - a pathogens
 - lungs
 - density
 - oxygen
 - Something that causes allergies
 - some viruses

Now knowing that amold spore has a negative impact on the respiratory system and molds and spores thrive in water-damaged furniture and carpets, choose the best answer.


 

  water-damaged carpets       