An IS auditor is analyzing a sample of accounts payable transactions for a specific vendor and identifies one transaction with a value five times as high as the average transaction. The next step that the auditor should do is to request an explanation of the variance from the auditee. This is because the variance may indicate an error, fraud, or an unusual but legitimate transaction that requires further investigation. The auditor should not report the variance immediately to the audit committee without verifying its cause and significance. The auditor should not increase the sample size to 100% of the population without considering the cost-benefit analysis and the sampling methodology. The auditor should not exclude the transaction from the sample population without justification, as itmay affect the validity and reliability of the audit results. References: CISA Review Manual (Digital Version), [ISACA Auditing Standards]

Comprehensive and Detailed Step-by-Step Explanation:
A key aspect ofbackup managementis ensuring backups are performed on time and without manual intervention to avoid human error.
* Option A (Incorrect):While separation of duties is important, the concern here is not aconflict of interestbut rather the reliability of backup execution.
* Option B (Incorrect):Load balancer configuration relates tonetwork traffic management, which is not directly relevant to backup reliability.
* Option C (Incorrect):Cloud-based backups can be a good option, but the immediate priority is toverify if backups are consistently executedbefore suggesting alternative solutions.
* Option D (Correct):Reviewing backup logs provides concreteevidenceof whether backups are performed on schedule and if they weremisseddue to peak usage periods. If issues are found, automation or scheduling adjustments may be recommended.
Reference:ISACA CISA Review Manual -Domain 4: Information Systems Operations and Business Resilience- Covers backup procedures, performance monitoring, and audit approaches.