Final answer:
Auditors document IT system controls using Internal control questionnaires, Systems flowcharts, and Written narratives to evaluate and describe the control environment and procedures.
Step-by-step explanation:
Auditors document their understanding of IT-based system controls primarily through the use of Internal control questionnaires, Systems flowcharts, and Written narratives. Although multiple select recordings of controls could be a method to list controls, it is not typically a standard way to document an understanding of the system controls in a formal audit context.
Internal control questionnaires (ICQs) allow auditors to assess control activities by asking specific yes/no questions about the control environment and control procedures. Systems flowcharts provide a visual representation of the systems, demonstrating how information flows through it and highlighting controls. Written narratives, also known as descriptive memos, furnish a detailed description of the system and the controls in place.