Final answer:
The theory that can explain fear at the sight of the dentist's office is classical conditioning, a part of behaviorism.
Step-by-step explanation:
A person who has had painful experiences at the dentist's office may become fearful at the mere sight of the dentist's office. The theory that can explain this is the classical conditioning theory, which is a part of behaviorism. According to this theory, the person's fear response is learned through association of the dental office (stimulus) with the painful experiences (response), resulting in fear being triggered by the sight of the dental office.
Classical conditioning was first studied by Russian physiologist Ivan Pavlov, who showed that animals and humans can learn to associate a neutral stimulus with an involuntary response. In this case, the painful experiences serve as the unconditioned stimulus, which naturally elicit fear as an unconditioned response. The dental office becomes the conditioned stimulus, which after repeated association with the painful experiences, can elicit fear as a conditioned response.