The correct option is A B > D > A > C
The time variation of the coalification process, as well as the depth at which the coal is found, affects the properties of coal.
PropertyPeatLigniteBituminousAnthraciteMoistureHighestHighRelatively lowerLowestHardnessSoftestSofterSoftHardestUpon burningSmokeSmokeSmokeSmokelessCarbon content<40%<40%40−90%>90%