What protects the brain by acting as a shock absorber and removing waste? Ventricles Skull Meninges Cerebrospinal fluid

The correct answer is:<br /><br />**Cerebrospinal fluid**<br /><br />### Explanation:<br />Cerebrospinal fluid (CSF) is a clear, colorless liquid that surrounds the brain and spinal cord. It serves several important functions, including:<br /><br />1. **Shock Absorption**: CSF acts as a cushion to protect the brain and spinal cord from impact or sudden movements.<br />2. **Waste Removal**: It helps remove waste products and toxins from the brain's metabolic processes.<br />3. **Nutrient Transport**: CSF delivers nutrients to the brain and removes waste through the circulatory system.<br />4. **Buoyancy**: It reduces the effective weight of the brain, preventing it from pressing down on the base of the skull.<br /><br />While the **skull** and **meninges** also provide physical protection for the brain, they do not perform the waste removal function. The **ventricles** are cavities in the brain where cerebrospinal fluid is produced and circulated, but they themselves do not act as shock absorbers or remove waste.