Answer:
Learned food aversion.
Step-by-step explanation:
The conditioned stimulus was a neutral stimulus before, and it became associated with the unconditioned stimulus.
For example, the smell of food is an unconditioned stimulus, while feeling of hunger is the unconditioned.
When we smell our favorite food, we also heard a horn honking. Horn honking is absolutely unrelated to the smell. But, if the sound of horn honking was paired with the smell of food many times, the sound alone would trigger the conditioned response. In this case, the sound of horn honking is the conditioned stimulus.
In this case:
Pizza -- unconditioned stimulus
Advertisement -- conditioned stimulus