Final answer:
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 known as the cost accounting information system.
Step-by-step explanation:
The correct answer is c. cost accounting information system. The cost accounting information system is designed to provide accurate and timely feedback concerning the performance of managers and others relative to their planning and control of activities. It focuses on the cost of activities and products and helps in budgeting, planning, and decision-making.