Cindy Creighton operates a real estate agency employing several sales representatives and property managers. The agency relies on a large volume of transactional and client information, with many enquiries managed by administration and support staff. Which of the following forms of systems documentation is likely to be most useful for Cindy to visualise her information system and identify when and how data is recorded? Select one: A. A system flow chart B. An enterprise resource planning diagram C. A business process diagram D. A data flow diagram