Which of the Following Is the Function of Cerebrospinal Fluid

Which of the following is the function of cerebrospinal fluid in the brain?

A) The function is not entirely clear and needs further research.
B) To support, nourish and clean the brain.
C) To lower the temperature of the brain.
D) To make a reservoir allowing for voluntary action.
E) To connect veins and arteries to the correct location in the brain.