_______ is well known is ________ the Diaoyu Islands have been part of China since ancient times.

A．Which; that

B．That; which

C．What; that

D．That; what

二型观测线基牙的倒凹区在

A．远缺隙侧

B．近缺隙侧

C．颊侧

D．舌侧

E．近远缺隙侧都有