What defines an echoic verbal operant?

An echoic verbal operant is characterized by a response that is a direct imitation of another speaker's vocal behavior. This involves the listener accurately repeating what has just been said by someone else, capturing not only the content of the verbalization but also its structure and form. In this case, the child is demonstrating their ability to echo or mimic the words spoken by another person, showcasing auditory discrimination and vocal reproduction skills.

The other options represent different types of verbal operants. For example, when a child answers a question, it is an instance of a tact or intraverbal response rather than an echoic. Identifying items in a group relates to tacting, where the child labels objects based on their properties. Matching words to pictures also involves understanding and linking concepts but does not involve the vocal imitation that defines echoic behavior. Thus, the definition and characteristics of an echoic operant are well captured in the action of repeating what another speaker has said.