—Do you enjoy My heart will go on?

—No, I prefer songs _____ loud.[ ]

A. that is

B. which is

C. that are

D. what are

支点线是指（）。

A．两个基牙的连线

B．两个卡环的连线

C．两个固位体的连线

D．两个支托的连线

E．两个主要基牙上直接固位体上支托的连线