Following the classical period, studies of the behavioral school’s current representatives are known as the micro-organization theory. The basic contribution of the behavioral school to the classical management theory is the emphasis on the informal aspects of organizations. While the classical management thought tackles the structural and physical design of organizations, the behavioral school focuses on human relations within organizations. The starting point of the behavioral school is the criticism that the classical school was not humanist and it regarded the human being as a machine, which makes it harder to increase productivity. Effectiveness and productivity, too,  are at stake in this period. However, the theorists mentioned try to explain that the human being has also a soul. So, the relations and situations within the organization are seen as variables that influence productivity. The most important studies within this field are Harwood and Hawthorne Experiments. Especially, Hawthorne concludes that productivity can only be increased by the emphasis on the emotional side of the human being and on managerial practices that make an employee feel important. In short, human behavior, human relations, motivation, managerial change, and development are the topics examined in this period, which maintained its importance until the 1960s. As also understood from the information given the correct answer is “C”. “The emphasis on the informal aspects of organizations” and “examining human behavior, human relations, motivation, managerial change, and development” are the basic contributions of the behavioral school to the classical management theory.  “Tackling the structural and physical design of organizations” is the contribution of the classical management thought. “taking the relationship of organizations with their environment into consideration” and “considering the organization as an open system” are the benefits of systems approach.