---I _________ stay up late. ---Really? I didn’t. But I ______ working in the night.

A．am used to, am used to

B．used to, used to

C．am used to, used to

D．used to, am used to

腰椎间盘突出症发病率最高的节段是（）

A.腰1～2

B.腰2～3

C.腰3～4

D.腰4～5

E.腰5～骶1