The first part of a classical conditioning experiment is typically a baseline phase, which is used to show that the stimulus that will be used as the conditioned stimulus is initially a/

The correct answer is unconditioned stimulus

Stimulus that elicits the unconditioned response. Its function is innate.

In classical conditioning, the unconditioned stimulus is one that unconditionally causes a natural and automatic response. For example, when you smell one of your favorite foods, you can immediately feel very hungry and salivate. In this example, the smell of the food is the unconditioned stimulus.