Final answer:
Henri Fayol's major functions of management are planning, organizing, leading, and controlling. Controlling is the function focused on monitoring organizational activities and ensuring they align with plans.
Step-by-step explanation:
According to Henri Fayol, the major functions of management are planning, organizing, leading, and controlling. Fayol identified these functions as the core to successful management and essential for establishing an effective organizational structure. The Theory X and Theory Y by McGregor also highlight the importance of management style in organizational behavior, contrasting an authoritative approach with a more participative style of leadership. The correct option, in this case, would be 'controlling', which focuses on ensuring that the organization's activities are proceeding as planned.