Which of the following produces cerebrospinal fluid $(CSF)$?

Consider the following statements regarding the human brain:
$1.$ The cerebrum has a highly convoluted surface,which provides space for more neurons.
$2.$ The medulla oblongata is connected to the spinal cord.
$3.$ The medulla oblongata contains centers for respiration,cardiovascular reflexes,and gastric secretions.
Which of the above statements are correct?

The $CNS$ is primarily composed of:

If someone receives a blow on the back of the neck, what would be the effect on the person's $CNS$?

Number of spinal nerves in rabbit is (in $pairs$)

Which of the following statements are correct about the cortex of the cerebrum? Choose the correct codes given below:
$(I)$. It consists of grey matter.
$(II)$. It shows prominent folds.
$(III)$. It consists of white matter.
$(IV)$. It contains motor areas,sensory areas,and association areas.