A risk register is a tool that records and tracks the identified risks, their causes, impacts, likelihood, responses, and owners. The owner for each risk scenario is the person or group who has the authority and accountability to manage the risk and its response. The best way to identify the owner for each risk scenario in a risk register is to map the identified risk factors to specific business processes. Risk factors are the internal and external variables that influence the occurrence and impact of risks. Business processes are the activities that produce value for the enterprise, such as sales, marketing, production, or delivery. By mapping the risk factors to the business processes, the risk practitioner can determine which business process is affected by or contributes to the risk, and who is responsible for the business process. The owner for each risk scenario should be the person or group who is responsible for the business process that is associated with the risk. The other options are not the best way to identify the owner for each risk scenario, as they involve different criteria or methods:
* Determining which departments contribute most to risk means that the risk practitioner evaluates the degree of involvement or exposure of each department to the risk. This may not be a reliable or consistent way to identify the owner for each risk scenario, as the risk may span across multiple departments, or the department may not have the authority or accountability to manage the risk.
* Allocating responsibility for risk factors equally to asset owners means that the risk practitioner assigns the same level of responsibility to each person or group who owns an asset that is affected by or contributes to the risk. An asset is a resource that has value for the enterprise, such as hardware, software, data, or people. This may not be a fair or effective way to identify the owner for each risk scenario, as the asset owners may have different levels of involvement or exposure to the risk, or may not have the authority or accountability to manage the risk.
* Determining resource dependency of assets means that the risk practitioner analyzes the relationship and interdependence of the assets that are affected by or contribute to the risk. This may help to identify the potential impact or likelihood of the risk, but it does not directly help to identify the owner for each risk scenario, as the resource dependency may not reflect the authority or accountability to manage the risk. References = Risk and Information Systems Control Study Manual, 7th Edition, Chapter 3, Section
3.1.1.1, pp. 95-96.

The main purpose of a risk register is to enable well-informed risk management decisions by providing a comprehensive and up-to-date record of all the identified risks, their analysis, and their responses. A risk register is a tool that helps to document, monitor, and communicate the status and outcome of risk management activities. A risk register also facilitates the review and evaluation of the effectiveness of risk management processes and controls. Documenting the risk universe, promoting an understanding of risk, and identifying stakeholders are possible benefits of a risk register, but they are not the main purpose. References
= Risk and Information Systems Control Study Manual, 7th Edition, Chapter 2, Section 2.1.1.3, page 531
1: ISACA Certified in Risk and Information Systems Control (CRISC) Exam Guide, Answer to Question
640.

According to the CRISC Review Manual1, threat impact analysis is the process of estimating and evaluating the potential effects of a threat event on the organization's objectives, processes, resources, and risks. Threat impact analysis helps to quantify and qualify the severity and likelihood of the threat, and to identify the possible consequences and implications for the organization. Communicating the results of the threat impact analysis is the most effective way to improve stakeholders' understanding of the effect of a potential threat, as it helps to inform and educate the stakeholders about the nature and magnitude of the threat, and to solicit their feedback and input for the risk response. Communicating the results of the threat impact analysis also helps to align the stakeholder expectations and preferences, and to facilitate risk-based decision making and action planning. References = CRISC Review Manual1, page 208.

Enterprise architecture (EA) documentation provides the most useful information to trace the impact of aggregated risk across the organization's technical environment, because it describes the structure and behavior of the organization's IT systems, applications, infrastructure, and processes, and how they support and enable the organization's strategy and objectives. EA documentation also defines the principles, standards, and guidelines that govern the design and implementation of the IT solutions and services.
Aggregated risk is the total or combined level of risk that the organization faces from multiple or interrelated sources or scenarios. Aggregated risk may have a greater impact than the sum of the individual risks, due to the synergistic or compounding effects of the risks. The technical environment is the set of IT components and capabilities that support the organization's business functions and processes. Tracing the impact of aggregated risk across the technical environment is a process of identifying and assessing the potential or actual consequences of the aggregated risk on the performance, functionality, or security of the IT systems, applications, infrastructure, or processes. EA documentation provides the most useful information, as it helps to understand and analyze the interdependencies and relationships of the IT components and capabilities, and to evaluate the effect of the aggregated risk on the alignment and integration of IT with the organization's strategy and objectives. Business case documentation, organizational risk appetite statement, and organizational hierarchy are all possible sources of information to trace the impact of aggregated risk, but they are not the most useful information, as they do not provide a comprehensive and detailed view of the technical environment and its architecture. References = Risk and Information Systems Control Study Manual, Chapter
5, Section 5.2.1, page 183

A benchmark analysis is a process of comparing the organization's performance, practices, and processes with those of other organizations in the same industry or sector. A benchmark analysis can provide the most useful information when determining the frequency of risk assessments, because it can help the organization to identify the best practices, standards, and expectations for security risk management in its industry. A benchmark analysis can also help the organization to assess its current level of maturity, capability, and compliance in relation to security risk management, and to determine the gaps and areas for improvement. By conducting a benchmark analysis, the organization can establish a realistic and appropriate frequency of risk assessments that aligns with its industry norms and its own risk profile. The other options are not as useful as a benchmark analysis, because they do not provide a comprehensive and relevant view of the security risk management landscape, but rather focus on specific or partial aspects of the organization's situation. References = Risk and Information Systems Control Study Manual, Chapter 1, Section 1.3.2, page
18.