The right answer avoids a brittle workaround. The best answer is A. Record-triggered flow. The selected option is not chosen because it sounds familiar; it is chosen because it gives Salesforce the right instruction at runtime. Lightning App Builder controls page composition, component visibility, activation, assignments, and specialized surfaces such as record pages, home pages, and utility bars.
The scenario describes a business outcome, not merely an administrative preference. If the feature is configured correctly, users get the intended result without depending on memory, spreadsheets, or manual policing. That is the professional standard for Platform App Builder work: place the rule in metadata, test it under the correct permissions, and keep the design supportable.
None of the other options gives the same administrative control. B (Validation rule) is only a partial match because A validation rule blocks saves; it does not create records, route approvals, display components, or grant access. C (Autolaunched flow) misses the mark because Flow is broad, but it is not correct unless the requirement is specifically about guided or automated logic. D (Quick action) is not enough: Actions improve user entry, but they are not a substitute for relationship modeling, reporting logic, or back-end automation.
This is the stronger design because it respects security, data quality, user experience, and lifecycle management at the same time.
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