(来学网)下列卡环中属于三类导线卡环的是
  • A.
    (来学网)正型卡环
  • B.
    (来学网)长臂卡环
  • C.
    (来学网)连续卡环
  • D.
    (来学网)锻丝上返卡环
  • E.
    (来学网)锻丝下返卡环