The lungs, nose, and trachea are organs of the respiratory system. All three help circulate oxygen through the body's system. *I might be wrong though*
The answer is B. they deliver oxygen to the blood.
Explanation:
Well air gets inside you to your lungs by your nose and mouth and once its inside your lungs travels that oxygen to your blood and takes "old" oxygen and releases it back out, all of this happens very quickly.
