因黄河中上游地区森林砍伐、牧场被开垦成耕地,自然植被破坏严重,黄河下游改道、迁徙成为常态。这种现象始于
A.公元5世纪
B.公元8世纪
C.公元10世纪
D.公元12世纪
正确答案是C
扫描二维码免费使用微信小程序搜题/刷题/查看解析。
版权声明:本文由翰林刷题小程序授权发布,如需转载请注明出处。
本文链接:https://doc.20230611.cn/post/456052.html
上一篇:Jogging is becoming one of the 21_____ growing activities in the nation. More people are starting jog each year. This, however, is a recent occurrence. It was not long ago 22_____ joggers were rare sight. Some people thought that they looked quite st
下一篇:使用EPROM应注意什么?