Final answer:
Scheduling workers is considered a directing activity for operations managers, as it involves guiding the daily tasks of employees, unlike planning or control activities such as selecting production equipment, product mix decisions, and inventory management.
Step-by-step explanation:
The responsibilities of operations managers encompass various activities that are generally categorized as planning, directing, or controlling. Among the options provided, scheduling workers is considered a directing activity. This involves overseeing and guiding the tasks and responsibilities of employees on a daily basis. Planning activities might include selecting production equipment, making product mix decisions, and designing the layout of production facilities because these deal with setting the groundwork for future operations. Control activities, such as inventory management, focus on monitoring and adjusting operations to meet predetermined standards and objectives. Directing is fundamentally about guiding the effort and work of employees.