In the face of unforeseen challenges and communication issues that have led to mistakes and delays, it is crucial for the project manager to engage directly with the team to discuss how project objectives can still be met. This involves open communication to understand the root causes of the issues, re-aligning the team's focus on the project goals, and collaboratively developing a plan to overcome the obstacles. This approach is supported by the PMBOKGuide, which emphasizes the importance of clear communication and stakeholder engagement in project management.
: The answer is corroborated by the principles found in the PMBOKGuide, which outlines the need for effective communication and stakeholder engagement throughout the project lifecycle. Additionally, the Professional in Business Analysis (PMI-PBA) reference materials highlight the significance of addressing challenges through teamwork and collaboration to ensure project success.

In the context of a project that involves new technology and an experienced Scrum team, the most suitable estimation technique is using story points. This method allows the team to leverage their collective experience and familiarity with each other's work to estimate the effort required for tasks relative to each other. Story points reflect the complexity, effort, and uncertainty of the task, making them ideal for projects where the technology is new and exact estimates are challenging to produce. Since the team has a history of successful collaboration, their established velocity can help predict how quickly they can work through the backlog.
: The use of story points is supported by Agile methodologies and is a common practice in Scrum teams for estimating work effort. This approach is detailed in the Agile Practice Guide, which is a complementary document to the PMBOK Guide, provided by PMI for understanding Agile practices in project management. The choice of story points over other estimation techniques is also consistent with the principles outlined in the PMI's Professional in Business Analysis (PBA) Reference Materials, which emphasize the importance of leveraging team expertise and past performance to inform project estimates.

Long user stories can hinder sprint completion and value delivery. The Scrum Master should facilitate a team review of the user stories and work with the product owner to ensure the stories are right-sized and follow the INVEST principle (Independent, Negotiable, Valuable, Estimable, Small, Testable).
Option A aligns with Scrum and Agile practices of team-based refinement and collaboration with the product owner.
Option B unnecessarily involves external stakeholders.
Option C puts the burden on one team member.
Option D promotes discussion but lacks action.
References:
Agile Practice Guide, Chapter 5 - Product Backlog Refinement
Scrum Guide - Sprint Planning and Story Sizing
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When a project experiences schedule delays, especially with tasks on the critical path, it is crucial to review the critical path with stakeholders. This collaborative review helps in understanding the impact of the delays and in defining the next steps to mitigate the issues. The stakeholders, including the project team, suppliers, and sponsor, can provide valuable input and decision-making power to help navigate the issues1.
References:
PMBOK Guide - Sixth Edition2.
"19 Frequently Asked Questions on the Critical Path Method" by Praveen Malik, PMP3.
"Exam PMP topic 1 question 321 discussion - ExamTopics"1.
"Five Tips for Being Prepared for Supply Chain Disruption" - PMI.org4.