**Core Concept**
The question is testing the knowledge of the autonomic nervous system, specifically the parasympathetic pathway to the parotid gland. The preganglionic parasympathetic fibers originate from the brainstem and synapse in a ganglion before reaching the target organ.

**Why the Correct Answer is Right**
The preganglionic parasympathetic fibers to the parotid gland synapse in the otic ganglion. The otic ganglion is a parasympathetic ganglion located near the foramen ovale, and it contains postganglionic neurons that synapse with the parotid gland. The preganglionic fibers originate from the glossopharyngeal nerve (cranial nerve IX) and travel to the otic ganglion, where they synapse with the postganglionic neurons. The postganglionic fibers then travel to the parotid gland and stimulate the secretion of saliva.

**Why Each Wrong Option is Incorrect**
* **Option A:** This is incorrect because the otic ganglion is the correct location for the preganglionic parasympathetic fibers to synapse.
* **Option B:** This is incorrect because the superior cervical ganglion is associated with the sympathetic nervous system, not the parasympathetic nervous system.
* **Option C:** This is incorrect because the ciliary ganglion is associated with the parasympathetic innervation of the eye, not the parotid gland.
* **Option D:** This is incorrect because the submandibular ganglion is associated with the parasympathetic innervation of the submandibular gland, not the parotid gland.

**Clinical Pearl / High-Yield Fact**
The otic ganglion is a small parasympathetic ganglion located near the foramen ovale, and it plays a crucial role in the parasympathetic innervation of the parotid gland. The preganglionic parasympathetic fibers to the parotid gland synapse in the otic ganglion, and the postganglionic fibers then travel to the parotid gland to stimulate the secretion of saliva.

**Correct Answer: C. Otic ganglion**