A benefits specialist's Project sometimes answers questions that the uploaded benefits documents don't cover, giving plausible but invented details. Which change to the Project instructions best addresses this?

Answer: C — Add: 'Answer only from the uploaded documents; if they don't cover it, say so and refer to the benefits team.'

A grounding rule plus an explicit fallback tells Claude what to do when the sources are silent (c). 'Be accurate' (a) is too vague to change behavior. Self-rated confidence (b) isn't a reliable accuracy signal. Adding generic outside articles (d) introduces non-authoritative sources that may not match the company's actual benefits.