(来学网)丝圈式保持器的丝圈与牙槽嵴之间的距离是
  • A.
    (来学网)0.1~0.5mm
  • B.
    (来学网)1.0~2.0mm
  • C.
    (来学网)3.0mm
  • D.
    (来学网)4.0mm
  • E.
    (来学网)5.0mm