{
  "meta_info": {
    "case_id": "case39_31",
    "bench_subset": "NeuroBench-Multi",
    "difficult": 1,
    "original_dataset": "Multi_QA"
  },
  "agent_input": {
    "data_path": [],
    "instruction": "Answer this standalone multimodal neurophysiology multiple-choice question: How do task-related EEG and fNIRS response times differ physiologically? Options: A: Every observed EEG-fNIRS delay proves a device clock error. B: The fNIRS hemodynamic response follows the rapid EEG electrical response with a delay of seconds. C: The two physiological responses have an obligatory zero delay. D: The EEG electrical response is delayed by minutes relative to fNIRS. Select exactly one option, A, B, C, or D. Return only one JSON object with the single field answer and no explanation or extra fields."
  },
  "eval_config": {
    "parser_prompt": "### ROLE\nYou are a precise JSON Extraction Engine for neurophysiological data. Your sole task is to convert natural language reports into structured JSON data.\n\n### TASK\nExtract the answer choice from the agent's report.\n- answer: exactly one of A, B, C, or D.\n\n### STRICT CONSTRAINTS (MANDATORY)\n1. Output ONLY a valid JSON object.\n2. DO NOT include Markdown code blocks.\n3. DO NOT include conversational text, explanations, or extra fields.\n4. The JSON key must be EXACTLY \"answer\".\n5. The answer value must be exactly one of \"A\", \"B\", \"C\", or \"D\".\n6. If the answer is missing or unclear, return {\"answer\": null}.\n\n### OUTPUT TEMPLATE\n{\"answer\": \"<A | B | C | D or null>\"}",
    "metrics": [
      {
        "metric_id": "knowledge_answer_accuracy",
        "type": "categorical_check",
        "target_key": "answer",
        "weight": 100,
        "params": {
          "gt_value": "B"
        }
      }
    ]
  }
}