Multiple choice Where does the oxygen carried through inhalation ultimately reach? Bronchioles Bronchus Trachea Alveoli Reveal answer Fill a bubble to check yourself D Correct answer Explanation Found in the lung parenchyma, the pulmonary alveoli are the terminal ends of the respiratory tree, which outcrop from either alveolar sacs or alveolar ducts, which are both sites of gas exchange with the blood as well.