第30题: [单项选择]Figures showed that security screeners were ______ dangerous items. A. able to detect B. not able to detect C. not effective in detecting D. very effective in detecting 参考答案:C 答案解析:题干问:Figures showed that security screeners were—dangerous items.在危险物品方面,数据显示安检仪:选项A说能检测;B说不能检测;C说不能高