Explanation
Brainstorming is a technique that allows the collection of the maximum number of ideas on a subject from a group without considering the validity or practicality of the ideas. The purpose of brainstorming is to generate as many ideas as possible in a short time, without judging or evaluating them. The ideas can be later prioritized, categorized, or refined by using other techniques. Interviewing is a technique that involves asking questions to individuals or groups to elicit information, opinions, or feedback. Prototyping is a technique that involves creating a model or a representation of a solution or a part of it to validate requirements, assumptions, or concepts. Surveying is a technique that involves collecting data from a large number of respondents using predefined questions and formats. References: Business Analysis for Practitioners: A Practice Guide, page
71-72; PMI Professional in Business Analysis (PMI-PBA)
Examination Content Outline, page 15.

Explanation
A requirements traceability matrix is a tool that shows the relationship between each requirement and other project elements, such as objectives, deliverables, test cases, design components, etc. A requirements traceability matrix can help the business analyst to determine the impact for the specific requirement change by showing how the change affects other related requirements and project elements. A requirements traceability matrix can also help to assess the feasibility, scope, value, and risk of the change request. References: = PMI Professional in Business Analysis (PMI-PBA)
Examination Content Outline
(2019), page 10; Business Analysis for Practitioners: A Practice Guide (2015), page 40.

Explanation
Root cause analysis is a technique that involves identifying and analyzing the underlying causes of a problem or an issue. Root cause analysis can help the business analyst to determine how the selection criteria requirement was missed, and to prevent similar errors from occurring in the future. Root cause analysis can be done using various tools, such as fishbone diagram and the Five Whys. A fishbone diagram is a graphical tool that organizes the possible causes of a problem into categories, such as people, process, technology, environment, etc. A fishbone diagram can help the business analyst to visualize the relationships between the causes and the effects, and to identify the most likely root causes. The Five Whys is a questioning technique that involves asking "why" repeatedly until the root cause of a problem is revealed. The Five Whys can help the business analyst to drill down into the details of the problem, and to uncover the underlying factors and assumptions that led to the missed requirement. : PMI Professional in Business Analysis (PMI-PBA)
Examination Content Outline1, page 21; Business Analysis for Practitioners: A Practice Guide2, page 101.

Explanation
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. References: = PMI Professional in Business Analysis (PMI-PBA)
Examination Content Outline
(2019), page 11; Business Analysis for Practitioners: A Practice Guide (2015), page 67.

Explanation
Communication is an essential part of requirements management, as it ensures that the requirements are clear, consistent, and agreed upon by all the project stakeholders. Stakeholders are the individuals or groups who have an interest or influence in the project, and who can provide input, feedback, and approval for the requirements. Communication also helps to avoid surprises, misunderstandings, and conflicts among the stakeholders, and to manage their expectations and satisfaction. Communication should be timely, accurate, relevant, and transparent, and should follow the communication plan and strategy defined in the requirements management plan12.
One of the aspects of communication is the status of the requirements, which indicates the progress and completion of the requirements throughout the project life cycle. The status of the requirements can be tracked and documented using a traceability matrix, which is a tool that links the requirements to their sources and traces them throughout the project. The status of the requirements can also be monitored and controlled using a change control process, which is a process that evaluates, approves, and implements any changes to the requirements. The status of the requirements can have different values, such as proposed, approved, implemented, verified, deferred, deleted, or rejected12.
When the status of a requirement changes, it should be communicated to all the project stakeholders, not just the source of the requirement or the project team. This is because the change in the status of a requirement may have an impact on the scope, schedule, cost, quality, or risk of the project, and may affect the interests or expectations of the stakeholders. Communicating the status of the requirements to all the project stakeholders helps to keep them informed and engaged, and to obtain their feedback and approval. It also helps to prevent surprises, such as the one experienced by the major stakeholder in the question, who was unaware that a particular requirement was deferred12.
Therefore, the best option is C. The status should have been communicated to all project stakeholders. Option A is not the best option, because the status should have been communicated to more than just the requirement's source. Option B is not the best option, because the status should have been communicated earlier than prior to project launch. Option D is not the best option, because updating the status in the traceability matrix is not enough, as the stakeholders may not have access to or awareness of the matrix.
References: 1 PMI Professional in Business Analysis (PMI-PBA)
Examination Content Outline, page
9-11; 2 Requirements Management 101 | Smartsheet 2