— Hello, Kate! Nice meeting you here! Working again, are you?

— Yes,          , if I want to pass the exams.

A．I’ve got to

B．I’m used to

C．I must do

D．I have one way

患者，男，12岁，直面型，面下1／3高度正常，上下前牙唇倾度正常，磨牙中性关系，Ⅱ度深覆牙合，覆盖3mm，上颌拥挤4mm，下颌拥挤5mm 。

该患者的拥挤程度为 （）

A.0度拥挤

B.Ⅰ度拥挤

C.Ⅱ度拥挤

D.Ⅲ度拥挤

E.以上都不是