Final answer:
Dr. Handy studies social psychology, which focuses on the influence of social interactions and societal factors on individual behaviors, thoughts, and feelings.
Step-by-step explanation:
Dr. Handy studies how other people influence our thoughts, feelings, and actions. Dr. Handy studies social psychology. This branch of psychology focuses on how social interactions and societal factors influence individuals' behaviors, thoughts, and feelings. It differs from other branches like cognitive psychology, which studies the internal processes related to thinking and cognition; developmental psychology, which looks at human growth and changes across the lifespan; and clinical psychology, which deals with the diagnosis and treatment of psychological disorders. The study of social psychology encompasses various aspects, such as group behavior, leadership, attitudes, prejudice, and interpersonal relationships.