Final answer:
Martin E.P. Seligman is known for emphasizing positive psychology, which focuses on human potential for happiness and well-being, as opposed to the determinism of behaviorism and psychoanalysis.
Step-by-step explanation:
Martin E.P. Seligman is best known for his contributions to the field of positive psychology, which focuses on fostering happiness and well-being, rather than just treating mental illness. This branch of psychology centers on what makes life most worth living and builds on inherent human strengths to help individuals and communities thrive. Seligman's work was a move away from the field's traditional emphases on behaviorism and psychoanalysis, tendencies which had dominated much of the 20th century.
While behaviorism and psychoanalysis provided important insights into human behavior, they were often criticized for their deterministic leanings. Behaviorism looked at human actions as completely shaped by environmental factors and genetics without the inclusion of free will, while psychoanalysis was focused heavily on the influence of unconscious drives and experiences. Seligman's positive psychology introduced a more optimistic view, emphasizing personal growth, altruism, and the inherent potential for happiness in all humans.
Therefore, Seligman felt the field of psychology should emphasize c) Positive psychology.