system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Lower border of pharynx is the level of:
assistant
The correct answer is  Pharynx, the upper portion of gut tube, is funnel-shaped fibromuscular tube that extends from the base of the skull to the inferior border of the cricoid cartilage at the level of C6 vertebra. 
It continues inferiorly as the esophagus.