Final answer:
The cost accounting information system is the subsystem that provides accurate and timely feedback on managerial performance concerning planning and control of activities.
Step-by-step explanation:
The cost management subsystem designed to provide accurate and timely feedback concerning the performance of managers and others relative to their planning and control of activities is the cost accounting information system. This subsystem is specifically aimed at tracking costs associated with production or service delivery, aiding in budgeting and performance evaluation, and providing cost data for decision-making purposes. Financial accounting information systems, while important for capturing the overall financial state of a company, are not solely focused on cost management. Operational control information systems deal with the day-to-day operations and not primarily with cost feedback and analysis, unlike cost accounting systems.