Final answer:
Mirror neurons are the type of neurons that allow newborns to imitate an adult sticking out their tongue.
Step-by-step explanation:
The certain class of neurons that makes it possible for newborns to imitate an adult who is sticking out his tongue are called mirror neurons.
Mirror neurons are special brain cells that enable mimicry and allow individuals to understand and imitate the actions of others. They are believed to be a fundamental prerequisite for language development.