题目

    A few years ago a young mother watched her husband diaper (给…换尿布) their firstborn son. “You do not have to be unhappy about it,” she protested. “You can talk to him and smile a little.” The father, who happened to be a psychologist, answered firmly, “He has nothing to say to me, and I have nothing to say to him.”     Psychologist now know how wrong that father was. From the moment of birth, a baby has a great deal to say to his parent and they to him. But a decade or so ago, these experts were describing the newborn as a primitive creature who reacted only by re设抛物线的顶点在原点，准线方程为，则抛物线的方程是 ____   （A）   （B）   (C)     (D)