可见光污染中,车站、机场等过多闪动的信号灯使人视觉不舒服,属于()。
A.灯光污染
B.其他可见光污染
C.视觉污染
D.眩光污染
参考答案:D
Great changes _________ in China in the last two decades.
A.have taken place
B.took place
C.have been taken place
D.are taking place
头颅血肿与产瘤的区别为()。