正解:C
The planning phase is crucial for any audit engagement and must be completed and approved before starting fieldwork. This ensures that the engagement has a clear scope, objectives, and methodology, which are necessary for conducting an effective and efficient audit. Without proper planning, the audit team may miss critical areas or waste resources on low-priority risks.
IIA References:
* IIA Standard 2200: Engagement Planning requires that internal auditors develop and document a plan for each engagement, including the engagement's objectives, scope, timing, and resource allocations, before starting fieldwork.
* The Practice Guide on Planning emphasizes that completing and approving the planning phase ensures that all necessary preparations are made, and potential risks are identified and mitigated before fieldwork begins.