**Core Concept**
Frey's syndrome, also known as gustatory sweating or auriculotemporal syndrome, is a rare neurological disorder that occurs as a complication of parotid gland surgery. It involves an aberrant regeneration of nerve fibers between the remaining parotid gland tissue and the auriculotemporal nerve, leading to inappropriate nerve signaling.

**Why the Correct Answer is Right**
The aberrant regeneration leads to the release of acetylcholine, a neurotransmitter typically involved in parasympathetic nervous system activity, in response to stimuli such as eating or salivation. This results in vasodilation of blood vessels and increased sweat gland activity, causing the characteristic symptoms of flushing and sweating. The auriculotemporal nerve, which carries both sensory and parasympathetic fibers, plays a crucial role in this aberrant regeneration.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Frey's syndrome is specifically related to aberrant regeneration of nerve fibers, not to a direct injury to the auriculotemporal nerve.

**Option B:** This option is incorrect because Frey's syndrome is not a result of parotid gland malignancy, but rather a complication of surgical procedures.

**Option C:** This option is incorrect because Frey's syndrome is not caused by a viral infection of the parotid gland, but rather by the aberrant regeneration of nerve fibers.

**Option D:** This option is incorrect because Frey's syndrome is not a result of a facial nerve injury, but rather a complication of parotid gland surgery.

**Clinical Pearl / High-Yield Fact**
A key feature of Frey's syndrome is the development of symptoms in the distribution of the auriculotemporal nerve, which includes the temporal region and the ear. This can be a useful clinical clue in diagnosing the condition.

**Correct Answer:** C.