What occurs when a conditioned response that had been extinguished reappears?

A. Spontaneous recovery

Spontaneous recovery is the phenomenon where a conditioned response that had been extinguished (meaning it was no longer triggered by the conditioned stimulus) reappears after a rest period. This suggests that the learned association is not completely forgotten and can resurface under certain conditions. Keep up the great work with your studies! If you have more questions or need further clarification, feel free to ask!