Final answer:
A psychologist who theorizes based on observable events and the influence of the environment on behavior is aligned with the behaviorist perspective.
Step-by-step explanation:
If a psychologist bases theories on measurable and observable events and believes that behavior is shaped by environmental forces, this psychologist has likely adopted the behaviorist viewpoint.
Behaviorists, such as B. F. Skinner, argue that personality is not inborn but rather formed through interactions with the environment.
They see behavior patterns as arising from learned reinforcements and consequences, rather than being the result of innate traits or unconscious processes. The focus on observable behavior and external stimuli distances behaviorism from other psychological perspectives such as psychoanalytic, which emphasizes unconscious processes, and humanistic, which focuses on personal growth and free will.