题目

Birth order, according to conventional wisdom, molds (塑造) personality; Firstborn children, secure with their place in the family, are expected to be mature and more responsible. Younger siblings (兄弟姐妹) work harder to get their parents’ attention and take more risk. That’s the central idea in psychologist Frank J. Sulloway’s “Born to Rebel”, an influential book on birth order.However, birth order does not appear to influence personality in adults, according to several ambitious studies published in the past few years, which relied on larger data sets and more statistical m一个物体在一对平衡力作用下，在光滑水平面上做匀速直线运动，这对平衡力突然消失，则物体将 [　　] A．立即停止运动B．运动速度越来越快 C．速度减慢，最后停止D．仍做匀速直线运动