Which person is NOT associated with the existential movement?

The correct answer is D, B.F. Skinner, because he is primarily associated with behaviorism, a psychological perspective that focuses on observable behaviors and the effects of reinforcement and punishment, rather than the philosophical underpinnings of human existence, freedom, and meaning that characterize existential therapy.

B.F. Skinner's work emphasized a scientific approach to understanding behavior through conditioning, which contrasts sharply with the existential focus on individual experience and the search for meaning in human life. In contrast, figures like Rollo May, Victor Frankl, and Irvin Yalom have made significant contributions to existential psychology by exploring themes such as anxiety, freedom, and the human capacity for self-realization. Their theories and approaches emphasize the importance of personal choice, responsibility, and the search for authentic existence, which aligns closely with the existential movement's objectives.