Any packet _____ properly will not be accepted by the post office. [ ]

A. not to address

B. not being addressed

C. not addressed

D. not having addressed

怀疑有下颌下腺导管结石，哪种X线片检查为首选（）

A.下颌骨侧位片十下颌横断颌片

B.下颌下腺造影

C.下颌体腔片

D.下颌曲面断层片

E.下颌下腺侧位片十下颌横断颌片