Update and expand the risk assessment report to address the authorizing official's specific concerns is correct.

The system owner is ultimately responsible for ensuring the risk assessment contains enough detail and clarity to support an authorization decision. By Update and expand the risk assessment report to address the authorizing official's specific concerns the owner can add clarifying scope definitions methodology descriptions evidence for findings impact and likelihood rationales and clear statements of mitigations and residual risk so the authorizing official can make an informed decision.

Updating the report is the most direct and timely way to resolve the deficiency because it preserves the original assessment work while filling gaps and documenting the rationale behind conclusions. That documentation becomes part of the authorization package and supports ongoing risk management and audit requirements.

Ask the information security officer for guidance is not the best sole action because asking for guidance does not by itself fix the lack of detail. Consulting the information security officer can be helpful for standards or review, but the owner must produce the improved assessment so the authorizing official's concerns are addressed.

Commission an independent third party to perform a new risk evaluation is usually unnecessary for a request for more detail and clarity. A third party evaluation adds cost and delay and is only justified if the original assessment is suspected to be biased compromised or fundamentally flawed.

Proceed with the authorization without addressing the identified gaps is inappropriate because the authorizing official has stated the assessment lacks sufficient detail. Proceeding without resolving those gaps could result in an uninformed risk decision and violate organizational or regulatory requirements.

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