Answer:
act as valves that allow CSF to pass from the subarachnoid space into the dural blood sinuses
Explanation:
Arachnoid granulation is the granular structure formed by the arachnoid cells which appear like invaginations in the dural venous sinuses.
The arachnoid forms the second layer or the middle layer of the brain which inner to the layer contains the subarachnoid space. In the subarachnoid space, the cerebrospinal fluid is present.
The arachnoid granulations act like one-way valves that allow the CSF to pass from the subarachnoid space to the venous sinuses.
Thus, the selected option is correct.
