三国两晋南北朝时期,江南经济逐渐赶上北方的原因有(   )①北

三国两晋南北朝时期,江南经济逐渐赶上北方的原因有  

①北方长期战乱,经济遭破坏

②大批北方农民南迁,增加了劳动力,带来了先进的技术

③南方较北方安定

④南北方人民的共同开发

A.①②③④   B.①②③   C.②③④  D.①②④

答案

A

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