—  Jack, I lost your ball at school. I suppose I should pay for it.  

— Oh. ______. It was just an old ball anyway.   [ ]

A. Take it easy    

B. By no means    

C. You got it        

D. Forget it

患者首诊的最佳处理措施是

A．牙周彻底洁治后，3%过氧化氢冲洗

B．去除大块的牙石及坏死物，3%过氧化氢冲洗

C．口服抗生素及维生素C

D．保守治疗，查血确诊

E．1%过氧化氢含漱1周