<prompt> Common carotid aery divides at the level ofHyoid boneCricoid cailageSuperior border of thyroid cailageInferior border of thyroid cailage  <response>: 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 