假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。错误涉及一个单词的添加、删除或修改。

增加：在缺词处加一个漏词符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1. 每处错误及修改均仅限一词；

2. 只允许修改10处，多者（从第11处起）不计分。One day a child was playing with a vase in great value. He careless put his hand into it. Hard as he tried, he could not pull it out. His father tried his best, too, but their efforts were in a vain. They were thinking of breaking the vase whenever the father said, “Now, my son, why have one more try? Open your hand or hold your fingers out straight as you saw I doing, and then pull.” To his surprise, the child says, “I can’t hold my fingers straight like that, because I don’t want to drop my penny.” Thousand of us sometimes are so busy hold on to the world’s worthless penny that we cannot achieve liberation.

根据数据库应用系统生命周期模型的描述，得到一个与计算机软硬件、DBMS的具体性能无关的全局概念模式——ER模型的阶段是

A．需求分析

B．概念设计

C．逻辑设计

D．物理设计