Where does the esophagus begin?

The esophagus begins at the level of the sixth cervical vertebra, commonly referred to as C6. Specifically, this anatomical landmark is where the pharynx transitions into the esophagus. This transition occurs as the muscular tube that forms the esophagus extends downward from the throat behind the trachea, allowing for the passage of food from the mouth into the digestive tract. Understanding the pathways in the neck and thoracic region is crucial for grasping how structures like the esophagus are positioned in relation to other anatomical features, such as the trachea and vertebrae.

The other options represent vertebral levels either above or below where the esophagus starts: C5, which is higher in the cervical region, T10, and T12, which are significantly lower in the thoracic and lumbar regions, respectively.