Risk tolerance is the most useful input when evaluating the appropriateness of risk responses, as it defines the acceptable level of risk for the organization and guides the selection of the optimal risk response. Incident reports, cost-benefit analysis, and control objectives are also useful inputs, but they are not the most useful, as they provide information on the actual or potential impact, cost, and effectiveness of the risk responses, but not the desired level of risk. References = CRISC Review Manual, 7th Edition, page 108.