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
Common carotid aery divides at the level of
assistant
The correct answer is  At the level of the upper border of the thyroid cailage, the aery ends by dividing into the external and internal carotid aeries. The right common carotid aery is a branch of the brachiocephalic aery. the left common carotid aery is branch of the arch of the aoa. Ref.BDC volume 3 sixth edition pg no: 99