**Core Concept**
The parasympathetic supply to the parotid gland is a part of the autonomic nervous system's salivary gland innervation. This involves the release of neurotransmitters that stimulate salivation, particularly acetylcholine, which acts on muscarinic receptors.

**Why the Correct Answer is Right**
The parasympathetic supply to the parotid gland originates from the glossopharyngeal nerve (cranial nerve IX), specifically through the otic ganglion. The preganglionic fibers from the glossopharyngeal nerve synapse in the otic ganglion, and postganglionic fibers then travel to the parotid gland to stimulate salivation. This pathway involves the release of acetylcholine, which acts on muscarinic receptors to increase salivary secretion.

**Why Each Wrong Option is Incorrect**
**Option A:** This is not a correct ganglion associated with the parasympathetic supply to the parotid gland.
**Option B:** This ganglion is not directly involved in the parasympathetic innervation of the parotid gland.
**Option C:** This option is incorrect as it is not a ganglion associated with the parasympathetic supply to the parotid gland.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the parasympathetic supply to the parotid gland originates from the glossopharyngeal nerve and involves the otic ganglion. This is a critical pathway for salivation and is often tested in exams.

**Correct Answer:** C. Otic ganglion