The correct answer is C. Elton Mayo.
The classical theorists were a group of management theorists who developed theories about how organizations should be structured and managed. They believed that organizations should be run in a rational and efficient manner, and that employees should be motivated by economic incentives.
Winslow Taylor was an American engineer who is considered the father of scientific management. He developed a system of management that focused on efficiency and productivity. Fayol, Crulik and Urwick were French engineers who developed a system of management that focused on the functions of management. Max Weber was a German sociologist who developed a system of management that focused on bureaucracy.
Elton Mayo was an Australian psychologist who is considered the father of human relations theory. He developed a system of management that focused on the social and psychological needs of employees.
The classical theorists had a significant impact on the development of management theory. Their ideas are still used in many organizations today. However, their theories have also been criticized for being too simplistic and for ignoring the human element of management.