The earliest psychologists, including William James (1890),

A. saw consciousness as a product of particular sets of neurons and neuronal pathways that may be activated in specific ways.
B. argued that consciousness could be understood only by relying "unscientifically" on the experiences of experimental participants.
C. rejected the idea that consciousness could be scientifically studied using several approaches.
D. suggested that the study of consciousness was central to the field of psychology.