Final answer:
The levator labii superioris, zygomaticus minor, and levator anguli oris are the three muscles responsible for lip elevation. These muscles are essential for expressing emotions through movements of the lips and corners of the mouth.
Step-by-step explanation:
The three muscles responsible for lip elevation are part of the muscles of facial expression. Specifically, these muscles are the levator labii superioris, which is primarily responsible for elevating the upper lip; the zygomaticus minor, which assists in lip elevation as well as producing expressions like smiling; and the levator anguli oris, which elevates the corners of the mouth.
Muscles of facial expression, including those that move the lips and the surrounding skin, perform important functions in nonverbal communication. The levator labii superioris, zygomaticus minor, and levator anguli oris together enable us to express emotions such as happiness, surprise, and disdain.