Bronchi are described as which?

• A. Three main branches at the top of the trachea
• B. Air sacs that participate in gas exchange
• C. The smallest airways in the lungs
• D. Two primary branches located at the lower end of the trachea that carry air into the lungs

Answer: (D)

Bronchi are the two main passages that split from the trachea and carry air into the lungs. This is why describing them as two primary branches located at the lower end of the trachea that enter the lungs is correct. They separate into the left and right main bronchi to route air into each lung. They are not air sacs involved in gas exchange (those are the alveoli), nor the smallest airways (those are the bronchioles).