What anatomical structures allow air to pass into or out of the lungs?

The correct choice is the conducting airways, which include structures such as the trachea, bronchi, and bronchioles. These airways serve as the passageways through which air travels to and from the lungs. The conducting airways are responsible for not only allowing air to enter the lungs during inhalation but also facilitating the exit of air during exhalation.

The alveoli, while crucial for gas exchange, are not the structures that transport air to and from the lungs; instead, they are the tiny air sacs where oxygen and carbon dioxide are exchanged with the blood.

Bronchioles also play an essential role within the conducting airways as they branch out from the bronchi and lead to the alveoli, but they are part of the broader category of conducting airways and do not encompass the entire pathway.

Capillaries, on the other hand, are tiny blood vessels that surround the alveoli and are involved in the exchange of gases between the blood and the inhaled air, but they do not function as passageways for air movement.

In summary, the conducting airways encompass the complete route for air movement into and out of the lungs, making them the correct answer to this question.