单选题 If this kind of machines had been invented earlier ,much more labor would have been saved.

【正确答案】 D
【答案解析】A)接近标准译文,只是句中被动语态过于直接,显的有些生硬。
B)march more labor would have been saved不能译成“人们就不用干更多的劳动”。
C)译文与原文不符合。
D)最佳译文。句中关键知识点虚拟语气翻译准确。