The aqueduct connects which ventricles?

• A. Lateral ventricles and third ventricle
• B. Third ventricle and fourth ventricle
• C. Fourth ventricle and subarachnoid space
• D. Connects the third and fourth ventricles

Answer: (B)

The cerebral aqueduct (aqueduct of Sylvius) is the narrow channel that carries CSF from the third ventricle down through the midbrain into the fourth ventricle. That makes the connection specifically between the third and fourth ventricles. The lateral ventricles communicate with the third ventricle through the foramina of Monro, not the aqueduct, and CSF exits the fourth ventricle into the subarachnoid space via the foramina of Luschka and Magendie, not through the aqueduct. So the best answer is the link between the third and fourth ventricles.