题目内容：

一些化学试剂瓶上贴有危险警告标志，下列物质的试剂瓶上所贴化学品标志有错误的是

                                   A                                   B                                   C                                   D

物质                          Na₂CO₃                         液氨                            浓H₂SO₄                     K₂Cr₂O₇

危险警告标识