At which vertebral level does the trachea bifurcate?

The correct answer is the vertebral level T4-T5, where the trachea bifurcates into the right and left main bronchi. This anatomical feature is significant in respiratory physiology and anatomy, as it marks the transition from the trachea, which is a singular airway, to the two branches that supply air to the lungs.

The bifurcation occurs approximately at the sternal angle, which is a palpable landmark on the anterior thorax where the manubrium meets the body of the sternum and corresponds closely to the T4-T5 intervertebral disc. Understanding this anatomical relationship is crucial for procedures involving airway management, such as intubation, and for interpreting imaging studies of the chest.

While other vertebral levels are referenced, they do not represent the correct location of bifurcation; each level indicates structures that correspond to different respiratory or cardiovascular features but not the tracheal division itself.