The best indication that key risk indicators (KRIs) should be revised is a decrease in the number of critical assets covered by risk thresholds. KRIs are metrics that provide information on the level of exposure to a given risk. Risk thresholds are the predefined values or ranges that indicate the acceptable or unacceptable level of risk exposure. Critical assets are the assets that are essential or vital for the achievement of the objectives or the continuity of the operations. A decrease in the number of critical assets covered by risk thresholds means that the KRIs are not capturing or reflecting the current and relevant risk exposure of the organization, and that they may not provide sufficient or accurate information for risk management decisions. Therefore, the KRIs should be revised to ensure that they cover all the critical assets and their risk thresholds.The other options are not as indicative as a decrease in the number of critical assets covered by risk thresholds, as they are related to the outcomes, impacts, or activities of the KRIs, not thescope or quality of the KRIs. References = Risk and Information Systems Control Study Manual, Chapter 4: Risk and Control Monitoring and Reporting, Section 4.2: Key Performance Indicators, page 183.