What enables the sympathetic and parasympathetic divisions to bring about opposing effects in most organs they impact?

A) postganglionic neurons in the sympathetic division release norepinephrine; postganglionic neurons in the parasympathetic division release acetylcholine
B) axons in the sympathetic division are myelinated while axons in the parasympathetic division are unmyelinated
C) the sympathetic division consists only of gray matter; the parasympathetic division consists only of white matter
D) the sympathetic division is associated with ganglia while the parasympathetic division does not involve ganglia