“火车教会人们守时,准时准点成了现代人生活的准则,人们开始要

“火车教会人们守时,准时准点成了现代人生活的准则,人们开始要随身带上一块表,时间概念是一个全新的概念。”这一现象最早出现于(    )

  A.蒸汽时代        B.电子时代         C.钢铁时代          D      络时代

答案

A

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