“治世不一道，便国不法古。故汤武不循古而王，夏殷不易礼而亡。反古者不可非，而循礼者不足多”。   

请回答：

①材料这段话应出自战国时期什么人之口？

②此人的主张是什么？代表哪个阶级？

③对我国现在的社会主义建设有何借鉴意义？

   ___  I could not remember the text .  [ ]

A. However hard did I try    

B. However hard I tried  

C. However I tried          

D. However had I tried hard