According to the PMI Guide to Business Analysis, a requirements traceability matrix is a tool that helps to ensure that the requirements are aligned with the business needs and objectives, and that they are verified and validated throughout the project life cycle. A requirements traceability matrix can also help to identify gaps, redundancies, and inconsistencies in the requirements. If the requirements matrix did not adequately track back to client requirements, it could result in a product that does not meet the client's expectations or specifications, even if it passes the test plan. Therefore, it is important to establish and maintain a clear and accurate traceability of requirements from their source to their implementation and verification.Reference: PMI Guide to Business Analysis, page 179-180.

A version control system is a tool that can be used to track requirements documentation. A version control system is a tool that allows the business analyst to manage and record changes to the requirements documentation throughout the project lifecycle. A version control system can help to ensure that the requirements documentation is consistent, accurate, and up-to-date. A version control system can also help to facilitate collaboration and communication among the team members and stakeholders who work on or use the requirements documentation. A version control system can also help to identify and resolve any conflicts or issues that may arise from concurrent or conflicting changes to the requirements documentation. An affinity diagram is not a tool that can be used to track requirements documentation. An affinity diagram is a technique that involves grouping similar or related ideas, issues, or data into categories based on their affinity or similarity. An affinity diagram can help to organize and analyze complex or diverse information, but it does not track or manage changes to the requirements documentation. A data dictionary is not a tool that can be used to track requirements documentation. A data dictionary is a tool that defines and describes the data elements and their attributes that are used or produced by a system or a solution. A data dictionary can help to standardize and clarify the meaning and usage of data elements, but it does not track or manage changes to the requirements documentation. A business rules matrix is not a tool that can be used to track requirements documentation. A business rules matrix is a tool that documents and organizes the business rules that govern or constrain a system or a solution.A business rules matrix can help to specify and communicate the logic and behavior of a system or a solution, but it does not track or manage changes to the requirements documentation.Reference: Business Analysis for Practitioners: A Practice Guide1, page 161-162; PMI Professional in Business Analysis (PMI-PBA) Examination Content Outline2, page 19-20.

Persona analysis is a technique that involves creating fictional characters that represent different user groups within the company. Persona analysis can help the business analyst to evaluate the solution's acceptance criteria by providing a detailed narrative of each user group's needs, goals, preferences, and behaviors. Persona analysis can also help to prioritize the requirements and design features that best suit each user group.Reference: = PMI Professional in Business Analysis (PMI-PBA) Examination Content Outline (2019), page 11; Business Analysis for Practitioners: A Practice Guide (2015), page 67.

The best approach to resolve this issue is to suggest re-estimating the requirement and following the change control process. This would allow the project team to assess the impact of the change request, evaluate the feasibility and cost of the modification, and obtain the approval of the stakeholders before implementing the change. A change control process is a method used to manage change requests for projects and big initiatives.It's part of a change management plan, which defines the roles for managing change within a team or company1. Meeting with the customer and apologizing for misunderstanding the business's need is not sufficient, as it does not address the root cause of the problem or propose a solution. Providing the stakeholder with a copy of the approved requirements baseline and moving forward without making a change is not acceptable, as it ignores the stakeholder's feedback and dissatisfaction.Requiring development resources to work overtime to modify the deliverable to satisfy the stakeholder is not advisable, as it may compromise the quality of the work, increase the project cost and risk, and demoralize the team.Reference: PMI Professional in Business Analysis (PMI-PBA) Examination Content Outline2, PMI Guide to Business Analysis3, Business Analysis for Practitioners: A Practice Guide4, What Is a Change Control Process?(with Example Change Log)

A change control process is a set of procedures that defines how changes to the requirements are identified, assessed, approved, implemented, and communicated. A change control process helps to ensure that changes are aligned with the business objectives, do not introduce unnecessary risks, and do not adversely affect the quality of the solution.A change control process also helps to manage stakeholder expectations and avoid scope creep.Reference: PMI Professional in Business Analysis (PMI-PBA) Examination Content Outline1, page 13; Business Analysis for Practitioners: A Practice Guide2, page 77.