Final answer:
In the described scenario, the child's utterance of "Ball" is a mand, which is a type of verbal behavior that serves as a request or command for something desired. It is not an intraverbal or a tact, which involve different communicative functions in ABA.
Step-by-step explanation:
In the scenario where a child says "Ball" and the RBT (Registered Behavior Technician) gives the child a ball, the word "ball" would be considered a mand. A mand is a type of verbal behavior in Applied Behavior Analysis (ABA) that is essentially a request or a command. When an individual uses a mand, they are asking for something that they want or need. In this instance, the child is using the word to request the ball, and the RBT is responding to this communication by fulfilling the request.
It is not an intraverbal, which involves a response to another's speech that does not directly correlate with a present stimulus or a specific motivation other than communication itself. Moreover, it is also not a tact, which would be labeling a present stimulus, such as commenting on the ball if it were in sight but not necessarily requesting it.