— The exam was easy, wasn't it?

— Yes, but I don't think _____ could pass it.                                                                                                                                    [      ]

A. somebody

B. anybody

C. nobody

D. everybody

史书记载：“古罗马士兵使用的刀剑是用熟铁制的，刺到敌人身上立刻弯曲，需放在地上用脚踩平再用。同一时期，我国的刀剑却锐利坚硬。”由此我们可以推断  [ ]

A．战国时期我国已能够造钢剑

B．同一时期我国战争更多

C．春秋时期我国出现灌钢技术

D．春秋时期我国铁制兵器完全取代青铜兵器