题目内容：

小明测得家庭常用物质的pH值如下表，其中碱性最强的是（   ）

                                     A                                  B                                  C                                   D

物质                            白醋                            牛奶                            鸡蛋清                        肥皂

pH                                3                                   6                                  8                                   10