A finding can be removed from the final audit report if management provides additional information that accurately contradicts the initial findings. This indicates that the initial findings may have been based on incomplete or incorrect information. Disagreements (Option A) or beliefs about the insignificance (Option D) of the finding do not justify removal unless they are supported by new, contradicting evidence. Even if corrective actions are already taken (Option B), the original finding may still be relevant for documentation and historical context.
IIA Standard 2410: Criteria for Communicating.
IIA Practice Guide on Communicating Results.

The frequency and approach to assessing residual risk are primarily influenced by the expectations set by the board and senior management. These expectations shape the internal audit function's priorities, including how often residual risk should be assessed and the methods used to evaluate it. This ensures that the internal audit activities are aligned with the strategic objectives and risk appetite of the organization, as defined by its senior leadership.
The Institute of Internal Auditors (IIA) - Standards for the Professional Practice of Internal Auditing, Standard
2120 - Risk Management

Verification of Controls: The auditor should verify that the new IT system addresses the previously identified risks. This involves reviewing the system documentation and ensuring that the controls in the new system effectively mitigate the risks.
IIA Standard 2500 - Monitoring Progress, which emphasizes the need for auditors to follow up on management's corrective actions.
Reporting: Once the auditor has confirmed that the new system controls address the risks, they can report to senior management and close the outstanding issue, ensuring that all audit recommendations are appropriately resolved.
Other Options:
Accepting Management's Explanation: Without verification (option B) is not appropriate as it may leave risks unmitigated.
Escalating Without Verification: Advising management and escalating (option C) is premature if the new system may already address the issues.
Detailed Process Evaluation: Requiring additional details about the process (option D) may be unnecessary if the auditor can verify the controls directly.

According to the IIA's guidance, internal audit can accept consulting engagements, including providing training, as long as it does not impair their independence and objectivity. In this scenario, the most appropriate action for the chief audit executive (CAE) is to accept the engagement and hire an external specialist to deliver the training. This ensures that the internal audit activity does not compromise its independence by training on areas where they might later need to provide objective assurance. By using an external expert, the CAE ensures the training is conducted by someone with the requisite expertise and without any conflict of interest.
The Institute of Internal Auditors (IIA), International Standards for the Professional Practice of Internal Auditing (Standards), Standard 1130: Impairment to Independence or Objectivity.
IIA Practice Guide, "Independence and Objectivity."

Valid closure of an audit observation requires evidence that the corrected process will function as expected in the future. This involves not just addressing the immediate condition but also ensuring that the root cause has been addressed and that the implemented corrective actions are sustainable and effective in preventing recurrence. This ensures that the underlying issue has been resolved comprehensively. References:
* The IIA's International Standards for the Professional Practice of Internal Auditing (Standards), Standard 2500 - Monitoring Progress.
* The IIA's Practice Guide on Audit Follow-up.