What collects blood within the brain and allows it to exit the skull?

• A. Arterial circulation
• B. Venous drainage system
• C. Venous circulation
• D. Lymphatic circulation

Answer: (C)

Blood leaves the brain through the venous drainage system. After the brain uses oxygen, the deoxygenated blood is collected by a network of veins and the dural venous sinuses, which channel it toward the internal jugular veins as they exit the skull. This venous drainage pathway is what removes blood from the brain, so venous circulation is the correct way to describe how blood exits the skull. Arterial circulation brings blood into the brain, not out of it. The lymphatic system isn’t the primary route for draining brain blood (it handles other clearance pathways, not the main venous outflow).