Answer:
Spontaneous recovery
Step-by-step explanation:
Spontaneous recovery can be defined as a phenomenon in which the object begins to display the behavior which was considered to be extinct. In such phenomenon, when a object is lessoned contioned response, and that response gets extincted, then it is known as spontaneous recovery.
In the given case, Jessie was lessoned with the condition response to stop blinking on the tone, which reappears when she entered the lab and heard the tone.
Therefore, spontaneous recovery is correct.