**Core Concept**: The parasympathetic nervous system plays a crucial role in regulating various physiological processes, including the control of salivary glands. The parotid salivary gland is a key example of this, as it is innervated by the parasympathetic nerves.

**Why the Correct Answer is Right**: The correct answer, C, states that the parasympathetic supply to the parotid salivary gland comes from the facial nerve (CN VII). The facial nerve is a mixed nerve that carries both motor and sensory information, but in this context, it is the parasympathetic component that supplies the parotid gland. This parasympathetic innervation is essential for the secretion of saliva from the parotid gland.

**Why Each Wrong Option is Incorrect**:

A. This option refers to the sympathetic supply to the parotid gland, which is derived from the superior salivary ganglion of the sympathetic chain. This is incorrect as the question specifically asks for the parasympathetic supply.

B. This option discusses the parasympathetic supply to the lacrimal gland, which is different from the parotid gland.

D. This option mentions the parasympathetic supply to the submandibular gland, another salivary gland, but not the parotid gland.

**Clinical Pearl**: Understanding the anatomy and innervation of the salivary glands is important as it helps in diagnosing and treating various disorders related to salivary gland function, such as Sjögren's syndrome, which can affect multiple salivary glands. In such cases, a thorough knowledge of the anatomy and innervation of salivary glands can aid in identifying the affected gland(s) and guiding appropriate diagnostic and therapeutic interventions.