The raphe system:
a. controls the sensory areas of the spinal cord.
b. is important for balance and coordination.
c. increases the brain's readiness to respond to stimuli.
d. regulates the rate of production of cerebrospinal fluid.

C

Explanation:

Raphe system is found in the brain. It regulates serotonin by decreasing it and functions as autoreceptors in the brain. The greater the brain auto receptors the greater the brain responds to and processes stimulus.

one centimetre is equal to 0.01 metres