Final answer:
It's true that sympathetic neurons feature short preganglionic fibers and long postganglionic fibers, which reflect their anatomical positioning and functions within the sympathetic nervous system.
Step-by-step explanation:
The statement that sympathetic neurons have short preganglionic fibers and long postganglionic fibers is true. In the sympathetic nervous system, most preganglionic neurons originate in the spinal cord, and because the sympathetic ganglia are located adjacent to the vertebral column, these preganglionic fibers are indeed relatively short and myelinated. On the other hand, postganglionic sympathetic fibers are long and unmyelinated because they have to extend a greater distance from the ganglion to reach the target organs or effector.