Regarding categorizing requirements for a user authentication application, which statement is most true?

Categorizing requirements is crucial for understanding, managing, and prioritizing them effectively. The notion that it's a good start and that groupings can be refined later acknowledges that requirements categorization is an iterative process. Initially grouping requirements allows project teams to gain clarity and focus on various aspects of user authentication, such as security, usability, and performance.

As the project progresses, it's recognized that the understanding of requirements may evolve. This flexibility to refine groupings means the team can adapt as deeper insights are gained or as different priorities emerge within the project lifecycle. For instance, feedback from stakeholders or changing market conditions might necessitate a re-evaluation of how certain requirements are grouped.

While categorization according to specification is important, it is more about aligning with standards and ensuring completeness rather than being the only framework in use. An initial categorization serves as a basis for further refinement, making option C the most practical and insightful about the requirements process for a user authentication application.