What accurately describes the anatomy of the Circle of Willis?

Correct answer is C) The Circle of Willis is an arterial circle formed by the anastomosis of the vertebral and internal carotid arteries. This circle provides a critical redundancy in cerebral blood supply, ensuring continuous perfusion to the brain even if one of the contributing vessels is compromised. A) Incorrect. The Circle of Willis is formed by branches of the vertebral and internal carotid arteries, not the external carotid arteries. B) Incorrect. The Circle of Willis is an arterial structure, not a venous one. It plays a role in maintaining arterial blood supply to the brain, not in venous drainage. D) Incorrect. The Circle of Willis is not related to lymphatic vessels; it is an arterial circle that plays a crucial role in regulating blood flow to the brain.