Answer:
The answer is the family parties.
Step-by-step explanation:
In classical conditioning, a conditioned stimulus (the smell of barbecue) is associated with an unrelated consequence, called unconditioned stimulus (the parties). This produces a reaction known as conditioned response (happiness).
It's important to recognise that unconditioned stimuli do not need a different stimulus to produce a response, but they can be paired with an unrelated object or situation in order to condition it.