John C. Calhoun--------hope this helps... rate me brainliest
Answer:
a conditioned stimulus
Explanation:
Ivan Pavlov was a great psychologist who has discovered the theory of classical conditioning while experimenting with dogs and has given a few important terms in the theory including conditioned and unconditioned stimulus and response.
Conditioned stimulus: According to Pavlov's experiment on classical conditioning, the term conditioned stimulus is defined as a formerly neutral stimulus after getting connected with an unconditioned stimulus gives rise to a conditioned response.
In the question above, the statement signifies that the sound of the bell is a conditioned stimulus.
Signal at least 100 ft before making a turn.
