In a situation where the budget is very tight, the best course of action for a project manager is to continuously monitor the project's budget and anticipate potential issues. This proactive approach allows the project manager to identify and address any financial concerns early on, preventing them from escalating into more significant problems. It aligns with the PMBOK Guide's principles of cost management, which emphasize the importance of planning, estimating, budgeting, and controlling costs to ensure that the project can be completed within the approved budget1.
: PMBOK Guide - Sixth Edition and other standards within the Project Management Institute's foundational standards1.

According to the PMBOK Guide, an agile approach is based on delivering value in small increments and iterations, rather than in one large deliverable at the end of the project1. This allows the project team to incorporate feedback, changes, and learning into the product or service, and to reduce rework and dissatisfaction2. Therefore, the project manager should adopt an incremental cycle of delivering value to the customer, and align the project objectives and scope with the customer needs and expectations. The other options are incorrect because:
* A. Decreasing the scope of the portfolio and sending new solutions to the customer is not an agile strategy, but a reactive one. It may imply that the project team is not able to deliver the agreed scope, or that they are not collaborating with the customer to understand their requirements and preferences.
* B. Delivering a schedule with the portfolio timeline and delivery to the customer is not an agile strategy, but a predictive one. It may imply that the project team is following a rigid and fixed plan, rather than responding to changes and uncertainties in the project environment.
* D. Preparing deliveries with more details to satisfy the customer is not an agile strategy, but a waterfall one. It may imply that the project team is focusing on documentation and specifications, rather than on working products and solutions. References:
* 1: PMBOK Guide, 6th edition, Chapter 1, Section 1.2.3, page 7
* 2: PMBOK Guide, 6th edition, Chapter 3, Section 3.8, page 52
* : Agile Practice Guide, Chapter 2, Section 2.1.1, page 13
* : Agile Practice Guide, Chapter 2, Section 2.2, page 14

The project manager should mentor the team to explain agile principles and create a shared understanding.
This will help the team to adopt an agile mindset, embrace the values and practices of agile approaches, and collaborate effectively throughout the project. The project manager should also provide feedback, coaching, and support to the team as they learn and apply agile methods. Evaluating the possibility of managing this project using a predictive approach, submitting a change request for a new team, and hiring a functional manager are not appropriate actions to address the situation, as they do not address the root cause of the confusion or help the team to develop agile competencies. References: = PMBOK Guide, 6th edition, pages
18-19, 27-28, 555-556; [Agile Practice Guide], pages 8-9, 13-14, 27-28; PMP Exam Content Outline, 2020, pages 6-7.

The Project Management Professional (PMP) certification emphasizes the importance of human resource management and the development of the project team. According to the PMBOK Guide, project managers should develop the team through training, team-building activities, and creating an environment that promotes high performance. In the scenario provided, where the team lacks experience, the project manager should utilize coaching and mentoring to bridge the experience gap, enhance skills, and improve team performance.
This aligns with the PMP's focus on leadership and the development of human resources within the project team.
: The references for this answer are drawn from the PMBOK Guide and the PMP Examination Content Outline, which detail the project manager's role in team development and the competencies required for effective project management. Additionally, the Professional in Business Analysis (PMI-PBA) reference materials support the approach of enhancing competencies through coaching and mentoring to ensure project success.

When a project budget is cut, it's important for the project manager to collaborate with the team to assess the impact of the change on the project1. This involves understanding how the budget cuts will affect different aspects of the project, including the scope, schedule, and quality. The project manager should then work with the team to develop an updated project plan that takes into account the reduced budget2. This approach aligns with the principles of servant leadership, which emphasize collaboration, team empowerment, and shared decision-making. References:
https://project-management.com/what-to-do-if-your-project-runs-over-budget-and-how-to-prevent-it/