The function of arachnoid granulations is to . The function of arachnoid granulations is to . allow the brain and spinal cord to "float" in CSF, preventing them from being crushed under their own weight act as valves that allow CSF to pass from the subarachnoid space into the dural blood sinuses circulate hormones between different parts of the CNS make associations between various kinds of sensory information help nourish the brain and spinal cord

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.

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