An organization has recently acquired and implemented intelligent-agent software for granting loans to customers. During the post-implementation review, which of the following would be the KEY procedure for the IS auditor to perform?

A. Review input and output control reports to verify the accuracy of the system decisions.
B. Review system documentation to ensure completeness.
C. Ensure that a detection system designed to verify transaction accuracy is included.
D. Review signed approvals to ensure responsibilities for decisions of the system are well-defined.