— Where was your brother at this time last night
— He was writing an e-mail ______ I was watching TV at home.

A. as soon as
B. after
C. until
D. while

张医生选择的人工牙，其上中切牙有以下特征：牙颈部略宽，近中面微凸，远中面的切1/2较凸，唇面较圆凸，两切角较圆钝

初戴全口义齿的吴某主诉义齿不稳定，临床检查见正中咬合时上下前牙水平开5mm，垂直距离增高。患者出现上述现象的原因是（）

A．颌位记录失误

B．排牙未达到正中平衡

C．义齿未达到前伸平衡

D．义齿未达到侧方平衡

E．患者有不良咬合习惯