A configuration management system is a tool that can be used to trace the large number of requirements that will be generated by this project. A configuration management system is a system that consists of the processes, procedures, tools, and databases that are used to manage and control the configuration items of the project. A configuration item is any component of the project that has a defined and approved version, such as a requirement, a deliverable, a document, a model, a test case, etc. A configuration management system can help the business analyst and the project team to record, track, update, and maintain the configuration items throughout the project lifecycle, and to ensure their consistency, integrity, and traceability. A configuration management system can also help to handle changes, resolve issues, and measure the quality and performance of the project. References: PMI Professional in Business Analysis (PMI-PBA)Examination Content Outline1, page 24; Business Analysis for Practitioners: A Practice Guide2, page 133.

Explanation
The business analyst can determine the impact of a new requirement on existing requirements by reviewing the requirements traceability matrix. The requirements traceability matrix is a tool that tracks the relationships and dependencies among the requirements, as well as other project elements such as design, test cases, risks, or issues. By reviewing the requirements traceability matrix, the business analyst can identify which existing requirements are affected by the new requirement and assess the impact of the change on the scope, schedule, cost, or quality of the project. Performing a stakeholder analysis is not a way to determine the impact of a new requirement on existing requirements, as it focuses on identifying and understanding the needs, expectations, and influence of the stakeholders, not the requirements. Using time-boxing to defer the new requirement is not a way to determine the impact of a new requirement on existing requirements, as it postpones the analysis and implementation of the new requirement until a later iteration or phase of the project. Updating the use case documentation is not a way to determine the impact of a new requirement on existing requirements, as it only reflects how the new requirement affects one aspect of the solution functionality, not the entire project. References: Business Analysis for Practitioners: A Practice Guide 1, page 161-162; PMI Professional in Business Analysis (PMI-PBA)
Examination Content Outline 2, page 19.

The type of requirements that do not trace to a business need are out-of-scope requirements. Out-of-scope requirements are the requirements that are not related to the project scope, objectives, or deliverables, and that do not contribute to the solution of the business problem or opportunity. Out-of-scope requirements are usually identified and excluded during the requirements analysis and traceability processes, to avoid wasting time, resources, and effort on unnecessary or irrelevant features or functions. Out-of-scope requirements can be caused by various factors, such as unclear or changing business needs, conflicting or unrealistic stakeholder expectations, poor communication or elicitation techniques, or lack of validation or verification methods. References: PMI Professional in Business Analysis (PMI-PBA)Examination Content Outline1, page 18; Business Analysis for Practitioners: A Practice Guide2, page 92.

A RACI matrix is a tool that defines the roles and responsibilities of stakeholders in a project or a process. It clarifies who is Responsible, Accountable, Consulted, and Informed for each task or deliverable. The business analyst should refer to the RACI matrix to identify who is responsible for signoff, as this person has the authority and accountability to approve the solution and its testing results. Contacting the sponsor, the stakeholder who provided the majority of requirements, or the project manager may not be appropriate, as they may not be the designated person for signoff according to the RACI matrix. No signoff is necessary is incorrect, as signoff is an important step to confirm that the solution meets the requirements and acceptance criteria. References: PMI Professional in Business Analysis (PMI-PBA)Examination Content Outline1, page 13; Business Analysis for Practitioners: A Practice Guide2, page 77.