题目

下面给出的四个命题中，是假命题的是（） A . 如果a＝3，那么|a|＝3 B . 如果(a－1)(a＋2)＝0，那么a－1＝0或a＋2＝0 C . 如果x2＝4，那么x＝2 D . 如果四边形ABCD是正方形，那么它是矩形 答案：C________ for the terrible accident, as the workers thought, the director felt nervous and was at a loss what to do. [     ]A. Having blamed  B. To blameC. Being to be blamed  D. Being to blame