I would say D. because exercise helps you sleep and concentrate, but it can also help fight depression. Trust me on the depression part ; )
Hope this helps!
The cerebrospinal fluid (CSF) is found within the brain, around the brain, within the spinal cord and around the spinal cord.
Explanation:
The CSF is the watery but clear fluid that circulates through the nervous system to protect the brain, spinal cord by providing a cushioning effect.
Within the brain, CSF is present in the hollow channels of ventricles and present surrounding the brain in the subarachnoid space.
It is also present within in the central canal that runs in the spinal cord and surrounding the spinal cord in the subarachinoid space.
CSF is mainly secreted in the choroid plexus present in the ventricles (lateral, third, fourth).
The flow of the CSF begins sequentially through the four ventricles and then the foramina in the brain, and then into the subarachnoid spaces around the brain and the spinal cord.
Im guessing you meant refusal skills, i hope. Refusal skills are a set of skills designed to help children avoid participating in high-risk behaviors. Programs designed to discourage crime, drug use, violence, and/or sexual activity frequently include refusal skills in their curricula to help students resist peer pressure while maintaining self-respect.
