Answer:
C. The smaller the particle, the deeper it can embed in lungs.
Step-by-step explanation:
As the lungs are filters for the air and oxygen that then is separated from the carbon dioxide which is later expelled to the air again, the smaller the particles, the easier that it is for the particle to get the deeper into the lungs, as the lungs filter, the smaller the particle the easire it passes throug those filters, so the correct option would be C. The smaller the particle, the deeper it can embed in lungs.