Nate is watching the cumulative recorder that is connected to a box where a rat is pressing a lever to receive food reinforcement. The slope of the line is becoming flatter and flatter over time. What can Nate conclude about the rat's response rate, based on this output?
◦ It is decreasing over time.
◦ It is increasing over time.
◦ It is caused by inadequate stimulus generalization.
◦ It will soon show spontaneous recovery.