(来学网)近距离治疗有效距离为
  • A.
    (来学网)5mm~10cm
  • B.
    (来学网)5mm~20cm
  • C.
    (来学网)5mm~5cm
  • D.
    (来学网)5m~15cm
  • E.
    (来学网)5~10mm