I'm not 100% certain because i know that doctors give folic acid to both a and b. However, I'm going to say C because the folic acid is putting a liner on your stomach so that when you do get pregnant there will be protection from certain medications. I hope this is the right answer for you.
B. because entry points are vital to the spread of infection
Attempting to collect the balance due at the time of service can serve for income purposes. It can guarantee that the doctors and the people involved with the procedure can get paid and the costumer will have the chance to access a proceudure. But actualy there are more disadvantages because the medical body can be sued and that they can not get paid if the patient does not feel that the procedure was good. It doesn't cover some expenses and it may not be comfortable neither for the patient nor for the doctors
Cerebrospinal fluid (CSF), clear, colourless liquid that fills and surrounds the brain and the spinal cord and provides a mechanical barrier against shock. Formed primarily in the ventricles of the brain, the cerebrospinal fluid supports the brain and provides lubrication between surrounding bones and the brain and spinal cord. When an individual suffers a head injury, the fluid acts as a cushion, dulling the force by distributing its impact. The fluid helps to maintain pressure within the cranium at a constant level.
https://www.britannica.com/science/cerebrospinal-fluid
