输入输出扩展机有（）两种类型
A、简单型和智能型
B、普通型和大型
C、简单型和复杂型
D、小型和大型
参考答案：A
What brings about the counter-clockwise swirling of the hurricane
A．The low-pressure area in the center of the storm.
B．The force of waves of water.
C．The trade winds.
D．The increasing heat.
开环聚合
