{
    "meta_info": {
        "case_id": "Q46",
        "bench_subset": "NeuroBench-Core",
        "difficult": 1.0,
        "original_dataset": "Core_QA",
        "references": "R20"
    },
    "agent_input": {
        "data_path": "",
        "instruction": "This is a standalone EEG/BCI knowledge multiple-choice question. No EEG data file is needed. Please answer by selecting exactly one option: A, B, C, or D.\n\nQuestion: What is one key difference between coherence and correlation?\nA. Correlation can only be used for gamma, whereas coherence can only be used for delta.\nB. Coherence is completely unaffected by volume conduction.\nC. Correlation necessarily implies causal connectivity.\nD. Coherence is a frequency-domain measure of linear coupling that can be evaluated at specific frequencies."
    },
    "eval_config": {
        "parser_prompt": "### ROLE\nYou are a precise JSON Extraction Engine for multiple-choice EEG/BCI QA responses. Your sole task is to extract the final selected answer option.\n\n### TASK\nExtract the final selected option from the agent report.\n\n### STRICT CONSTRAINTS (MANDATORY)\n1. Output ONLY a valid JSON object.\n2. DO NOT include Markdown code blocks.\n3. DO NOT include any conversational text, explanations, or units.\n4. The key must be EXACTLY \"selected_option\".\n5. The value must be one of \"A\", \"B\", \"C\", \"D\", or null.\n6. If multiple options are mentioned, extract only the final answer option.\n7. If the selected option is missing or unclear, return {\"selected_option\": null}.\n\n### OUTPUT TEMPLATE\n{\"selected_option\": <string|null>}",
        "metrics": [
            {
                "metric_id": "qa_option_accuracy",
                "type": "categorical_check",
                "target_key": "selected_option",
                "weight": 100,
                "params": {
                    "gt_value": "D"
                }
            }
        ]
    }
}