Frey's syndrome, also known as gustatory sweating, is a condition that occurs due to the damage and abnormal regeneration of nerve fibers. In Frey's syndrome, the nerve commonly involved is the auriculotemporal nerve. This nerve is responsible for carrying parasympathetic secretomotor fibers to the parotid gland and sympathetic fibers to the sweat glands. Damage to it can lead to improper cross-connection, resulting in sweating and flushing on the cheek during eating.
In summary, the correct answer to the question, "Nerve injured in Frey’s syndrome is:" is: