The correct option is Preserving auditors' independence and impartiality.

Preserving auditors' independence and impartiality is essential because independence underpins the credibility and trustworthiness of any external review. An independent auditor can report findings without undue influence or conflict of interest and stakeholders can rely on the conclusions. Evidence sources and tools support the audit but they cannot substitute for an impartial examiner who evaluates evidence and reaches conclusions in good faith.

Reviewing immutable Cloud Audit Logs and exported records is important as a source of evidence but it is not the most essential factor by itself. Logs can help establish facts but they still require independent analysis and proper access controls to ensure the logs were not altered or selectively presented.

Granting auditors broad administrative access across projects for convenience is wrong because convenience can create conflicts and increase risk. Auditors should be given a clearly defined scope with controlled read only or monitored access so that they can remain impartial and the integrity of the environment is preserved.

Using automated posture and vulnerability tools such as Security Command Center is valuable for identifying issues and collecting evidence but it does not guarantee impartial conclusions. Automated tools assist the audit process but they do not replace the need for independent judgement and validation by the auditor.

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