Sympathetic preganglionic neurons originate in which spinal segments?

• A. T1-L2
• B. S2-S4
• C. C1-C4
• D. L4-L5

Answer: (A)

The main idea here is that the sympathetic preganglionic neurons come from the thoracolumbar region of the spinal cord. Their cell bodies reside in the intermediolateral cell column from T1 through L2. From there, the preganglionic fibers exit the spinal cord and enter the sympathetic chain or prevertebral ganglia to synapse with postganglionic neurons that distribute to various organs.

That’s why this option is correct: the thoracic and upper lumbar segments form the sympathetic outflow. The sacral segments (S2–S4) are parasympathetic preganglionic origins, not sympathetic. The cervical segments (C1–C4) do not house sympathetic preganglionic cell bodies, and the lower lumbar segments beyond L2 (like L4–L5) lie outside the typical thoracolumbar range for sympathetic outflow.