The circle of arteries at the base of the brain that supplies blood to the brain is also known as the Circle of Willis.

• A. Cerebral arterial ring
• B. Circle of Willis
• C. Basilar circle
• D. Circle of Circulation

Answer: (C)

The structure at the base of the brain that forms a circular network of arteries supplying cerebral blood is known as the Circle of Willis, also called the cerebral arterial circle. It is built from the internal carotid arteries, the anterior cerebral arteries joined by the anterior communicating artery, the posterior cerebral arteries connected via the posterior communicating arteries, and the basilar artery contributing to the posterior side. This arrangement creates a protective loop that allows blood to flow from multiple vessels to all parts of the brain, providing collateral circulation if one pathway is narrowed or blocked. Other terms like basilar circle or circle of circulation aren’t the standard name for this structure, and cerebral arterial ring is descriptive but not the formal designation.