--- How do we say the number “4056 ”? ---                  

A．four thousand , fifty- six

B．four thousand and fifty- six

C．four zero five six

D．four thousand fifty and six

桩核冠修复中，对残冠牙体的错误处理是

A．平齐龈 * * 连线截断

B．去除薄壁

C．去除无基釉

D．去除腐质

E．以上都对