Question

Select the answer below that best describes how the lungs are kept free of germs and dirt in the air

Answer 1

your options are not given

Answer 2

The oxygen we breathe enters the human body through trachea, the trachea further branches into the bronchial tubes that contains mucus in it. This mucus collects all the germs and the dirt entering the lungs via air.  Moreover, Cilia, the tiny hairs keeps the lungs clean by sweeping out all kinds of debris.