The firstman to define psychology "as the science of behaviour" was

Solution(By Examveda Team)

The correct answer is option C. J.B. Watson.

J.B. Watson was the first man to define psychology "as the science of behavior." He is considered one of the key founders of behaviorism, a psychological approach that focuses on studying observable behavior rather than internal mental processes. Watson believed that psychology should focus solely on objective, measurable behavior and rejected the study of subjective experiences or consciousness.

Watson's influential work, particularly his 1913 paper "Psychology as the Behaviorist Views It," emphasized the importance of studying observable behavior and its environmental determinants. He believed that behavior could be understood and predicted by examining the stimulus-response relationship and the conditioning processes that shape behavior.

Option A, Wilhelm Wundt, is often considered the founder of psychology as an experimental science. Wundt established the first psychological laboratory in Leipzig, Germany, in 1879 and focused on the study of conscious experience through introspection.

Option B, William McDougall, was an influential psychologist known for his work in the field of comparative psychology and instinct theory. He emphasized the role of inherited instincts and subjective experiences in shaping behavior.

Option D, William James, was an influential American philosopher and psychologist. While James did not define psychology specifically as the science of behavior, he made significant contributions to the field, including his influential book "The Principles of Psychology," published in 1890.

Therefore, the correct answer is option C. J.B. Watson, as he was the first to define psychology as the science of behavior and was a key figure in the development of behaviorism.