The first branch from the trachea is the ________.

A) alveoli
B) hilus
C) secondary bronchus
D) primary bronchus

Primary Bronchus

One of the two main branches of the trachea that lead directly into the lungs, conducting air in and out.

Secondary Bronchus

A branch of the primary bronchus that further divides into smaller airways in the lungs, known as tertiary bronchi.

Hilus

The part of an organ where blood vessels, nerves, and other structures enter or exit, commonly referenced in the context of the lungs and kidneys.