{
  "id": "S209",
  "type": "单选题",
  "type_code": "single",
  "stem": "连续生产的电子管厂，产品质量检验是这样安排的，在一天中，每隔半小时抽取一次产品进行检验，这是（ ）。",
  "stem_text": "连续生产的电子管厂，产品质量检验是这样安排的，在一天中，每隔半小时抽取一次产品进行检验，这是（ ）。",
  "options": [
    {
      "key": "A",
      "text": "分层抽样"
    },
    {
      "key": "B",
      "text": "简单随机抽样"
    },
    {
      "key": "C",
      "text": "整群抽样"
    },
    {
      "key": "D",
      "text": "系统抽样"
    }
  ],
  "options_text": [
    {
      "key": "A",
      "text": "分层抽样"
    },
    {
      "key": "B",
      "text": "简单随机抽样"
    },
    {
      "key": "C",
      "text": "整群抽样"
    },
    {
      "key": "D",
      "text": "系统抽样"
    }
  ],
  "answer_keys": [
    "D"
  ],
  "answer_display": "D",
  "answer_texts": [
    "系统抽样"
  ],
  "sources": [
    {
      "edition": "第15届",
      "edition_num": 15,
      "no": 39,
      "uid": "15-039",
      "file": "第15届市调大赛本科组模拟题1.docx"
    },
    {
      "edition": "第17届",
      "edition_num": 17,
      "no": 40,
      "uid": "17-040",
      "file": "17届市调大赛本科组模拟题.docx"
    }
  ],
  "source_display": "第15届 第39题、第17届 第40题",
  "source_count": 2,
  "images": [],
  "warnings": [],
  "conflict": null,
  "url": "/q/S209.html"
}