The auditor must gather sufficient and appropriate evidence during the course of the audit. Appropriate eve O A. be well documented and cross-referenced in the audit documentation files maintained by the auditor. B. be based on the possibility that the auditor can obtain additional corroborative evidence if original evidence cannot be depended upon solely O C. provide pertinent and believable evidence that determines which audit procedures to use. D. provide accounting data that help the auditor to prove or disprove the audit objectives set by the auditor to examine management assertions