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. References: Business Analysis for Practitioners: A Practice Guide 1, page 161-162; PMI Professional in Business Analysis (PMI-PBA)Examination Content Outline 2, page 19-20.