After deploying conversational search, an engineer notices the assistant occasionally returns AI-generated answers that are irrelevant to the user's question. They want the assistant to show a 'no answer found' message when retrieved passages are below a certain relevance score. Which setting should be adjusted?

The search integration in watsonx Assistant includes a configurable confidence threshold. When the relevance scores of retrieved passages fall below this threshold, the assistant suppresses the AI-generated answer and can surface a fallback response instead. This prevents the LLM from generating responses from poorly matched content. The correct answer, "Configure the search integration's confidence threshold to require a minimum relevance score before displaying AI-generated responses", directly satisfies the scenario because it aligns with watsonx Assistant's design principles and the specific capability being tested. The incorrect options ("Lower the NLU intent confidence threshold to prevent weak intents from triggering search", "Reduce the top-K search results to 1 so only the single best passage is used", "Disable LLM response generation entirely and display raw search excerpts instead") may appear relevant but each misses a key requirement or introduces a step that is either unnecessary or belongs to a different workflow. Mastering the distinction between these approaches is essential for effective watsonx Assistant implementations and is a core focus of the Domain 4: Integrate with watsonx section of the certification exam.