(来学网)根据ISO规定,口腔用铸造金合金的含金量及铂族金属(Pt、Pd、Ir、Rh、Ru、Os等)的量应不少于
  • A.
    (来学网)50%
  • B.
    (来学网)55%
  • C.
    (来学网)65%
  • D.
    (来学网)75%
  • E.
    (来学网)85%
正确答案:
D