The best way to mitigate the risk to IT infrastructure availability is to establish a disaster recovery plan (DRP), because a DRP is a document that defines the procedures and resources needed to restore the IT infrastructure and resume the critical business functions in the event of a disaster or disruption. A DRP helps to minimize the downtime, data loss, and financial impact of a disaster, and ensures the continuity of operations and services. The other options are not the best ways to mitigate the risk to IT infrastructure availability, although they may also be helpful in supporting the DRP. Establishing recovery time objectives (RTOs), maintaining a current list of staff contact details, and maintaining a risk register are examples of planning or monitoring activities that aim to define the requirements, roles, and responsibilities for the disaster recovery process, but they do not address the actual implementation or execution of the DRP. References = CRISC: Certified in Risk & Information Systems Control Sample Questions

A risk action plan is a document that outlines the actions to be taken to mitigate or avoid a risk. A risk action plan should be revised when the risk associated with a new technology is found to be increasing, as this indicates that the current plan is not effective or sufficient. Revising the risk action plan can help identify the root causes of the risk increase, evaluate the effectiveness of current controls, and implement additional or alternative controls as needed. Re-evaluating current controls, escalating the risk to senior management, and implementing additional controls are possible steps in the revision process, but they are not the first course of action. The first course of action should be to update the risk action plan to reflect the current risk situation and the appropriate risk response.

A change management process is a set of procedures and activities that aim to ensure that changes in an organization's IT systems and services are implemented in a controlled and coordinated manner. The effectiveness of a change management process can be measured by how well it reduces the risks and costs associated with changes, and how well it supports the business objectives and customer expectations. One of the best metrics to demonstrate the effectiveness of a change management process is the percent of unauthorized changes. Unauthorized changes are changes that are made without following the established change management process, such as obtaining approval, documenting the change, testing the change, and communicating the change. Unauthorized changes can introduce errors, defects, security breaches, and disruptions to the IT systems and services, and can negatively affect the business performance and customer satisfaction. Therefore, a low percent of unauthorized changes indicates that the change management process is effective in ensuring that changes are properly planned, approved, executed, and monitored. The other options are not the best metrics to demonstrate the effectiveness of a change management process, as they do not directly reflect the quality and control of the changes. An increase in the frequency of changes may indicate that the organization is agile and responsive to the changing business needs and customer demands, but it does not necessarily mean that the changes are well-managed and beneficial. An increase in the number of emergency changes may indicate that the organization is able to handle urgent and critical situations, but it may also suggest that the organization is reactive and lacks proper planning and analysis of the changes. The average time to complete changes may indicate the efficiency and speed of the change management process, but it does not measure the effectiveness and value of the changes. References = CRISC Review Manual, pages 156-1571; CRISC Review Questions, Answers & Explanations Manual, page 712

According to the CRISC Review Manual1, the risk register is a tool that records the results of risk identification, analysis, evaluation, and treatment. The risk register should be populated as soon as possible in the risk management process, to capture and document the risks and their attributes. The best time for the risk practitioner to start populating the risk register is when identifying risk scenarios, as this is the first step in the risk identification process. Risk scenarios are hypothetical situations that describe the potential causes, impacts, and responses of a risk event. Identifying risk scenarios helps to generate a comprehensive and relevant list of risks that can be recorded in the risk register. References = CRISC Review Manual1, page 191,
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