A:Must; must
B:Can; must
C:Must; must have
D:Can; must have
秦《峄山刻石》中说:“追念乱世,分土建邦,以开争理。攻战日作,流血于野,自泰古始,世无万数,陀及五帝,莫能禁止。”秦始皇针对上述问题采取的措施是( )