Final answer:
Dual processing research, which explores conscious and unconscious cognitive processes, shares similarities with the levels of consciousness described by Sigmund Freud. Therefore, among the listed psychologists, Freud's work relates most to the concept of dual processing.
Step-by-step explanation:
Research into dual processing supports the notion that we have different levels of consciousness. This idea resembles the concepts described by Sigmund Freud, a pivotal figure in psychology. Freud theorized about the unconscious mind and believed that much of our behavior is influenced by unconscious drives and experiences.
Freud's model of the mind included various levels of consciousness, including the conscious, preconscious, and unconscious. Dual processing research, which concerns the operation of both conscious and unconscious processes simultaneously, fits nicely with some of Freud's ideas. Essentially, this body of research suggests that we are only partially aware of the vast complexities of cognitive operations that govern our behavior and mental processes.
Thus, in response to the student's question regarding the psychologist whose levels of consciousness are somewhat echoed in dual processing theory, the answer is c. Sigmund Freud.