According to the PMBOK Guide, consensus decision-making is a technique that ensures that all input and ideas from a group or team are considered until a final decision that is acceptable to all emerges. This approach relies heavily on respectful dialogue and open-mindedness, and it is often used to build consensus regarding the requirements in project management. By organizing a face-to-face meeting with all stakeholders, the project manager can facilitate the communication and collaboration among them, and elicit their needs, expectations, and preferences. This can help to resolve any conflicts or contradictions, and reach a common understanding of the project requirements. References:
* PMBOK Guide, Sixth Edition, Chapter 5, Section 5.2.2.4
* How to use Consensus Decision-Making for Project Management by Grace Windsor

In an agile framework, it is beneficial to review the completion costs of similar projects as it provides a realistic baseline for the new project's cost estimation. This approach is supported by the PMBOK guide, which suggests using historical information and lessons learned from similar projects to inform cost estimations1. Additionally, involving the client representative (option A) is also a good practice in agile projects to ensure that the estimation aligns with the client's expectations and priorities2. However, the primary action should be to review similar past projects for a more accurate estimation.
: The PMBOK Guide outlines the importance of utilizing historical data and information from similar projects when estimating costs3. The PMP Examination Content Outline also emphasizes the use of past project data for cost estimation in agile project environments1. The Professional in Business Analysis Reference Materials further support this approach, highlighting the value of lessons learned and historical analysis in project cost management4.

Expert judgment is a technique that uses the knowledge and experience of experts to identify risks in a project. Experts can be internal or external to the project team, and they can provide insights on the sources, causes, and effects of potential risks. Expert judgment can also help to assess the probability and impact of risks, as well as the appropriate responses to them. According to the PMBOK Guide, expert judgment is one of the tools and techniques for the Identify Risks process, which is part of the Project Risk Management knowledge area. The other tools and techniques are data gathering, data analysis, interpersonal and team skills, and prompt lists. The other options are not tools and techniques for the Identify Risks process, although they may be used in other risk management processes or activities. An analysis of shared risks between parties is a way of identifying common risks that affect multiple stakeholders or projects. A SWOT analysis is a strategic planning tool that evaluates the strengths, weaknesses, opportunities, and threats of a project or organization. A risk value assessment is a method of prioritizing risks based on their expected value, which is the product of their probability and impact. References:
* PMBOK Guide, 6th edition, pages 397-398, 419-420
* Project Management Professional (PMP) Certification Handbook, page 9
* Risk Identification in Project Management, section "PMP Risk Identification Lifecycle"

The project manager should inform the sponsor and document the request in the stakeholder engagement plan, as this is the best way to handle the situation without compromising the project scope, budget, or schedule.
The sponsor can then decide how to deal with the key stakeholder's request, and the project manager can update the stakeholder engagement plan accordingly. This will also help the project manager to maintain a positive relationship with the key stakeholder and avoid any potential conflicts or misunderstandings.

Comprehensive and Detailed Explanation:
In global virtual teams, active listening and adaptability are key leadership traits. By engaging the team, understanding their communication challenges, and adjusting practices accordingly, the project manager demonstrates empathy and responsiveness-essential for building trust and reducing conflict.
* A is passive and may be perceived as blaming.
* B is useful but not the first response.
* D is a leadership principle but too broad without specific action.
* C addresses the root issue and aligns with servant leadership behaviors.
References:
* PMBOK Guide - Seventh Edition, Communication and Team Performance Domains
* PMI's Leadership and Communication Skills Competency Framework
Here are the verified answers and full explanations for PMP Questions 1835 to 1838, formatted as requested:
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