Answer:
The name of the section in the dragon dance where the dragon's head is moved up and down is called the Head Bobbing section.
In this section, the dancer controlling the dragon's head moves the head up and down while keeping the rest of the body still, creating a bobbing motion that mimics the movement of a real dragon. This movement is often accompanied by the sound of drums or cymbals to enhance the visual effect.
The Head Bobbing section is an important part of the dragon dance performance, as it adds variety and interest to the overall routine. It also serves to emphasize the dragon's power and strength, as well as its graceful movements.