An employee self-service assistant answers pay questions. Its HR database tool runs under a service account that can read every employee's record. The system prompt says the assistant must never reveal another employee's salary. Security asks for the strongest control against a leak. What is the most appropriate design?

Answer: B — Scope the tool to the requesting employee's own record using their identity, so other records can't be fetched

(b) is right: a zero-tolerance rule needs enforcement outside the model, and removing the ability to fetch other records is stronger than any check on what the model says. (a) and (d) are prompt-level controls that make a leak rarer but not impossible. (c) detects leaks after they've happened rather than preventing them.