Parasympathetic fibers from the EW nucleus synapse with which ganglion before innervating the iris sphincter and ciliary muscle?

• A. Ciliary ganglion
• B. Pterygopalatine ganglion
• C. Otic ganglion
• D. Submandibular ganglion

Answer: (A)

The parasympathetic output that constricts the pupil and facilitates accommodation travels from the Edinger‑Westphal nucleus with the oculomotor nerve and stops to synapse at the ciliary ganglion. After this synapse, postganglionic fibers ride the short ciliary nerves to the iris sphincter and ciliary muscle, producing pupil constriction and lens accommodation. The ciliary ganglion is the specific relay for this ocular parasympathetic pathway, so it’s the correct site of synapse.

Other parasympathetic ganglia listed serve different targets (pterygopalatine for lacrimal and nasal glands, otic for the parotid, submandibular for the submandibular/sublingual glands) and aren’t involved in innervating the pupil or ciliary muscle, which is why they don’t fit this pathway.