A critical patch is a software update that fixes a security vulnerability or a bug that may affect the performance, functionality, or reliability of a system or a network. A critical patch implementation is a process that applies the software update to the system or network in a timely and effective manner. The failure of a critical patch implementation is a situation where the software update is not applied or not applied correctly, which may expose the system or networkto various threats, such as data theft, data corruption, data leakage, or denial of service. The failure of a critical patch implementation would be reflected in an organization’s risk profile by increasing the residual risk. Residual risk is the risk that remains after the risk response, which means the risk that is not avoided, transferred, or mitigated by the existing controls or measures. The failure of a critical patch implementation would increase the residual risk, as it would reduce the effectiveness or efficiency of the existing controls or measures that are supposed to address the security vulnerability or the bug. The failure of a critical patch implementation would also increase the likelihood or impact of the potential threats, as well as the exposure or consequences of the system or network. The other options are not the correct changes that would be reflected in an organization’s risk profile after the failure of a critical patch implementation, although they may be affected or related. Risk tolerance is the degree of variation from the risk appetite that the organization is not willing to accept. Risk tolerance may be decreased by the failure of a critical patch implementation, as the organization may become more cautious or conservative in accepting the risk, but it is not a direct or immediate change in the risk profile. Inherent risk is the risk that exists in the absence of any controls or measures, which means the risk that is inherent to the system or network or the environment. Inherent risk may be increased by the failure of a critical patch implementation, as the system or network may become more vulnerable or susceptible to the threats, but it is not a change in the risk profile, as the risk profile considers the existing controls or measures. Risk appetite is the amount and type of risk that the organization is willing to accept in pursuit of its objectives. Risk appetite may be decreasedby the failure of a critical patch implementation, as the organization may become less willing orable to accept the risk, but it is not a change in the risk profile, as the risk profile reflects the actual or current risk level, not the desired or expected risk level. References = CRISC Review Manual, pages 32-331; CRISC Review Questions, Answers & Explanations Manual, page 972; What is a Critical Patch? - Definition from Techopedia3; What is Residual Risk? - Definition from Techopedia4