Final answer:
The cell bodies of preganglionic neurons are found in both the brain stem and the sacral region of the spinal cord for both the sympathetic and parasympathetic divisions of the autonomic nervous system.
Step-by-step explanation:
The statement that the cell bodies of preganglionic neurons are found either in the brain stem or in the sacral region of the spinal cord is true for both divisions of the autonomic nervous system.
For the sympathetic division, most preganglionic neurons originate in the spinal cord and release acetylcholine on postganglionic neurons within sympathetic ganglia located alongside the spinal cord.
For the parasympathetic division, preganglionic neurons are located in the brain stem and the lateral horn of the sacral spinal cord. These preganglionic fibers release acetylcholine onto the postganglionic neurons, which then contact the target tissues within the organs.