A . 薄煤层不低于97%,中厚煤层不低于95%,厚煤层不低于93%
B . 薄煤层不低于75%,中厚煤层不低于65%,厚煤层不低于55%
C . 薄煤层不低于85%,中厚煤层不低于80%,厚煤层不低于75%
D . 薄煤层不低于93%,中厚煤层不低于85%,厚煤层不低于80%