乘车时遇到急刹车，右膝前方受到撞击，出现右髋剧痛，髋关节运动障碍，处子屈曲、内收、内旋畸形状态。该患者治疗4周后，自行下地负重行走，正常活动，预计可能发生下列哪一种情况

A．股骨头缺血性坏死

B．关节强直

C．髋关节周围创伤性骨化

D．习惯性关节脱位

E．关节周围组织损伤

In low - speed network ,it is usually adequate to wait for congestion to occur and then react to it by telling the source of packets to slow down. In high - speed networks, this approach often works poorly, because in the (71) between sending the notification and notification arriving at the source, thousands of additional (72) may arrive. In ATM network , a major tool for preventing (73) is (74) control. When a host wants a new virtual (75) ,it must describe the traffic to be offered and the service expected.

A．collision

B．congestion

C．drop

D．delay