Explanation
According to the PMBOK Guide, 6th edition, Section 11.4.3.1, Risk Thresholds, risk thresholds are the level of risk exposure above which risks are addressed and below which risks may be accepted. Risk thresholds are determined by the organization's risk appetite, which is the degree of uncertainty that an organization is willing to accept in pursuit of its goals. Therefore, when the project manager is informed by the risk owner that the exposure from two high-impact risks are hitting the risk thresholds, the project manager should complete an assessment and confirm the response with the sponsors, who are the key stakeholders for the project and have a low risk appetite. The project manager should not update the project management plan, perform an assumptions and constraints analysis, or implement mitigation measures without first consulting with the sponsors and obtaining their approval. References: PMBOK Guide, 6th edition, Section 11.4.3.1, Risk Thresholds

Explanation
Risk impact assessment involves calculating the impact of identified risks. Risk analysis is the process of examining, estimating, and evaluating the impact of risks, which helps in calculating the impact (Reference:
PMBOK Guide, 6th Edition, p. 417)
Risk analysis is the process of assessing the likelihood and impact of the identified risks on the program objectives. It helps to calculate the impact of the risks by using qualitative or quantitative methods. Risk analysis can provide useful information for risk prioritization, risk response planning, and risk reporting.
References: PMI, The Standard for Risk Management in Portfolios, Programs, and Projects, 2019, p. 67; PMI, The Standard for Program Management, Fourth Edition, 2017, p. 113.

Explanation
The project manager should consult or review project contracts, lessons learned registers from analogous projects, and the risk management plan to develop an effective risk planning for the project.
According to the PMBOK Guide, the risk management plan is one of the key inputs for the plan risk management process, which is the first process in the project risk management knowledge area. The risk management plan describes how risk management activities will be structured and performed throughout the project. It includes information such as the methodology, roles and responsibilities, budget, timing, risk categories, definitions of risk probability and impact, probability and impact matrix, revised stakeholders' risk tolerances, reporting formats, and tracking (page 409). Therefore, option D is the correct answer.
The project contracts are also an important input for the plan risk management process, as they may contain terms and conditions that can create or affect various project risks. For example, contracts may include clauses related to penalties, incentives, warranties, intellectual property rights, termination, force majeure, arbitration, indemnification, etc. The project manager should review the project contracts to identify any potential sources of risk and plan appropriate responses (page 410). Therefore, option A is the correct answer.
The lessons learned registers from analogous projects are another valuable input for the plan risk management process, as they provide historical information and knowledge that can help the project manager identify and analyze risks, as well as plan risk responses. The lessons learned registers may contain information such as the risks that occurred, the root causes of the risks, the risk triggers, the effectiveness of the risk responses, the residual and secondary risks, the risk owners, the risk ratings, the risk trends, etc. The project manager should consult the lessons learned registers from similar or comparable projects to learn from past experiences and avoid repeating mistakes (page 411). Therefore, option B is the correct answer.
The risk register is not an input for the plan risk management process, but an output. The risk register is a document that contains the list of identified risks, their causes, potential responses, and other relevant information. The risk register is created during the identify risks process, which is the second process in the project risk management knowledge area. The risk register is then updated and refined throughout the project as more information becomes available and new risks emerge (page 414). Therefore, option C is incorrect.
The code of regulations is not an input for the plan risk management process, but a type of enterprise environmental factor. Enterprise environmental factors are the conditions, not under the control of the project team, that influence, constrain, or direct the project. The code of regulations refers to the rules and standards that govern the project's industry, domain, or sector. The code of regulations may affect the project's scope, schedule, cost, quality, resources, communications, procurement, and risk management. The project manager should consider the code of regulations when planning risk management activities, but it is not an artifact that needs to be reviewed or consulted (page 38). Therefore, option E is incorrect.
References: PMBOK Guide, pages 38, 409-411, 4141

Explanation
The project charter is the first resource the project manager should reference to determine the risk tolerance and risk attitudes of the project's key stakeholders, as it contains information such as the project purpose, objectives, success criteria, high-level risks, and key stakeholder list. The project charter is an output of the Develop Project Charter process, which is part of the Initiating process group. The project charter provides the project manager with the authority to apply organizational resources to project activities and establishes a partnership between the performing organization and the requesting organization. References: PMBOK Guide,
6th edition, page 81-82.
Enterprise environmental factors (EEFs) provide information about the organization's culture, risk tolerance, and risk attitudes, which can help the project manager determine the risk tolerance and risk attitudes of the project's key stakeholders. (Reference: PMBOK Guide, 6th Edition, p. 39)

Explanation
Residual risks are the risks that remain after the risk response plan has been implemented. They are the risks that are accepted by the project team and stakeholders as part of the project. Residual risks may have low probability or impact, but they still need to be monitored and controlled throughout the project. The first thing that the risk manager should do when a risk owner identifies and reports some residual risks is to analyze, document, and communicate them to the relevant stakeholders. The risk manager should assess the probability and impact of the residual risks, and determine if they require any further response or contingency plan. The risk manager should also update the risk register and the risk report with the information about the residual risks, and share them with the stakeholders who need to be aware of them. This will help the project team and stakeholders to be prepared for any potential occurrence of the residual risks, and to take appropriate actions if needed. References: PMI, The Standard for Risk Management in Portfolios, Programs, and Projects, 2019, p.
94-95, 101.