As air moves down through the tracheobronchial tree, the FIRST segment that will contain alveoli will be ________.

A) terminal bronchioles
B) alveolar duct
C) alveolar sac
D) bronchioles
E) respiratory bronchioles

Alveoli

Alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place.

Tracheobronchial Tree

The structure comprising the trachea and branching bronchi, facilitating air passage to the lungs.

Terminal Bronchioles

The smallest air passages in the lungs before the alveolar ducts, involved in the process of air distribution and gas exchange.