The correct answer is C. Human relation approach.

The Hawthorne experiments were a series of studies conducted at the Hawthorne Works of the Western Electric Company between 1924 and 1932. The experiments were designed to study the relationship between working conditions and productivity. However, the results of the experiments were surprising. The researchers found that productivity increased regardless of whether working conditions were improved or worsened. This led to the conclusion that social factors, such as worker morale and satisfaction, were more important than working conditions in determining productivity.

The Hawthorne experiments led to the development of the human relations approach to management. This approach emphasizes the importance of employee satisfaction and motivation in achieving organizational goals. It also stresses the need for managers to create a positive work environment and to provide employees with opportunities for participation and growth.

The system approach, human behavior approach, and process approach are all different approaches to management. The system approach views the organization as a system of interrelated parts. The human behavior approach focuses on the individual employee and his or her behavior in the workplace. The process approach emphasizes the importance of planning, organizing, leading, and controlling in achieving organizational goals.

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