Final answer:
Rinsing the mouth protector with mouthwash before each use is NOT appropriate when caring for it.
Step-by-step explanation:
Of the given instructions, rinsing the mouth protector with mouthwash before each use is NOT appropriate when caring for the mouth protector. While it may seem like a good idea to use mouthwash to clean the mouth protector, it is not necessary and may even be harmful. Mouthwash often contains alcohol and other chemicals that could damage the mouth protector or irritate the mouth.