The trachea divides into right and left mainstem at the?

• A. Hyoid bone
• B. Carina
• C. Vallecula
• D. Parenchyma

Answer: (B)

The division point of the trachea into the right and left main bronchi is the carina, a cartilaginous ridge inside the lower trachea. It sits at about the level of the sternal angle (roughly T4–T5). This landmark matters in airway management because endotracheal tubes should be placed above the carina to ensure both lungs are ventilated; going too far can preferentially ventilate one lung by entering a mainstem bronchus. The other structures—hyoid bone, vallecula, and parenchyma—are not where the trachea splits: the hyoid is higher in the neck, the vallecula is the space between the tongue and epiglottis, and parenchyma refers to lung tissue.