题目

His conflicted with that of the other witnesses and yet his story had, for me, the ring of truth. A . expectation B . instruction C . response D . account 答案：D某厂生产的2000件产品中，有不合格产品m件，今分10次各抽取50件产品进行检测，平均有不合格产品1件，对的叙述正确的是 （   ） A．                              B． C．的值应在40左右                    D．无法确定