—Judy,  you look so tired.

—Yes, I didn't go to bed ____ 12 o'clock last night.    [ ]

A. when    

B. unless    

C. until    

D. after

诊断颌下腺导管结石，拟拍X线片时，首选何种方法

A．颌下腺造影

B．下颌骨侧位片

C．下颌曲面断层

D．颌下腺侧位+下颌横断颌片

E．下颌体腔