Through which structure is cerebrospinal fluid (CSF) directly drained into the venous circulation?

Explanation

Cerebrospinal fluid is absorbed into the venous system primarily via the arachnoid villi (also called arachnoid granulations), which protrude into the dural venous sinuses. The choroid plexus produces CSF but does not return it to the venous blood. Cerebral veins and emissary veins are involved in venous drainage but do not directly absorb CSF.