Answer: C. An establishing operation
Explanation: An establishing operation is a motivating operation that amplifies an action, it can be a stimulus or an event. This practically means that such an operation increases the value of, for example, a stimulus or event that is constantly repeated at a certain time - a dinner for the dog. Dinner for the dog at a certain time is a stimulus for the dog, which is enhanced by the motivating, i.e establishing operation of not feeding the dog during the day. This again means that in the dog due to the lack of feeding during the day (establishing operation) increases the value of food and therefore the dog, which did not eat during the day, is consequently hungry when the time comes for dinner, and thus increases the reaction, i.e the dog accesses food and eats all of his dinner.