The selected design maps to Implement a hybrid memory system with vector-based search and key-value storage to retrieve relevant past interactions, which is the highest-control path for this scenario rather than a prompt-only or single-service shortcut. For knowledge-grounded agents, the clean architecture is a RAG path with retrievers and vector indexes externalized from the LLM, then evaluated for retrieval quality and answer faithfulness. Agentic systems need explicit decomposition: a planner or coordinator defines the work, specialized agents or tools execute bounded actions, and memory/state is preserved only where it improves the next decision. That structure increases maintainability because each agent role, message contract, and state transition can be tested independently under load. The distractors are weaker because they lean on A: Use a sliding window of recent conversation tokens in memory to track...; B: Retrain the model periodically using historical logs to improve long-term contextual understanding; D: Increase the maximum context window size so the full conversation history is..., which compromises traceability, resilience, scalability, or policy enforcement in production. The answer therefore fits NVIDIA's production-agent pattern: modular workflow design, measurable runtime behavior, GPU-aware serving where applicable, and controlled integration with enterprise systems.