In the context of project management, particularly within the PMBOK Guide's framework, it is crucial for a project manager to address conflicts by identifying and addressing the root causes. This approach aligns with the conflict resolution techniques outlined in the PMBOK, which include problem-solving and collaboration as effective methods for resolving disputes. By engaging stakeholders to understand their perspectives and reach a consensus, the project manager can facilitate a collaborative environment that fosters mutual understanding and agreement on how to move forward.
(PMBOK Guide - Sixth Edition, Chapter 13: Project Stakeholder Management)

When a change request is received, it is essential for the project manager to conduct an impact analysis to understand how the proposed change will affect the project's scope, schedule, cost, and quality. This analysis is a critical step before moving forward with any decisions regarding the change request. It allows the project manager to make an informed decision and to discuss the change with all relevant stakeholders, including the functional manager who submitted the request.
: The process for managing change requests is outlined in the PMBOKGuide, which includes the steps of identifying, analyzing, and documenting the change request before presenting it to the Change Control Board (CCB) for approval1. The Professional in Business Analysis Reference Materials also emphasize the importance of impact analysis as part of the change management process234.

According to the PMBOK Guide, the project manager is responsible for managing the project team and ensuring that the team members are motivated, engaged, and productive. One of the tools and techniques for managing the project team is interpersonal and team skills, which include communication, conflict management, emotional intelligence, feedback, influence, mentoring, and motivation. When a team member feels demotivated and excluded from the team, the project manager should first use their interpersonal and team skills to speak with the team member and understand the root cause of their dissatisfaction. The project manager should also acknowledge the team member's contributions and provide constructive feedback and guidance to help them improve their performance and engagement. This will help the team member feel valued, respected, and supported by the project manager and the team. References: PMBOK Guide, 6th edition, pages 349-350, 355-356.

Before implementing any new directive, especially during an ongoing project, the project manager must first assess its potential impact on project performance, delivery timeline, and team morale. PMI promotes the use of decision-making based on impact analysis and objective evaluation.
According to the PMBOK Guide - Seventh Edition (Measurement and Planning Performance Domains), project managers must ensure that metrics align with performance goals and do not create disruptions.
Option B is helpful but premature before understanding the implications.
Option C assumes disruption without validating it.
Option D postpones compliance and could violate governance expectations.
References:
PMBOK Guide - Seventh Edition, Measurement Performance Domain
PMI Governance of Portfolios, Programs, and Projects Framework
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