I regret _______ you that the tickets ______ .

A．telling, have sold out

B．to tell, has sold out

C．to tell, have been sold out

D．telling, have been sold out

按Black窝洞分类第Ⅳ类洞为：（）

A、开始于窝沟的洞

B、后牙邻面洞

C、前牙邻面洞不包括切角

D、前牙邻面洞包括切角

E、牙齿唇、颊或舌面颈三分之一的洞