A ring of multiple arteries which provides alternate bloodflow pathways and guards the brain against damage is called:

Correct option is C

The Circle of Willis is an anatomical ring of arteries at the base of the brain that connects major cerebral arteries, providing collateral circulation and alternate pathways for blood flow if one artery becomes blocked.

Information Booster:
• The Circle of Willis is formed by the anterior cerebral arteries, anterior communicating artery, internal carotid arteries, posterior cerebral arteries, and posterior communicating arteries
• This arterial ring provides redundancy in blood supply—if one pathway is blocked, blood can flow through alternate routes
• It helps protect the brain from ischemic damage by ensuring continuous blood supply even during arterial occlusion
• Approximately 50% of people have anatomical variations in their Circle of Willis
• The structure is crucial during stroke assessment and neurosurgical planning
• Named after Thomas Willis, the 17th-century physician who first described it

Additional Knowledge:
• (A) Cranium: The skull bones that protect the brain, not a vascular structure
• (B) Meninges: Three protective membrane layers (dura mater, arachnoid mater, pia mater) surrounding the brain and spinal cord, not arteries
• (D) Blood Brain Barrier: A selective semipermeable border that separates blood from brain tissue, controlling which substances enter the brain—not an arterial structure