What is the name given to a class of coal that contains a high percentage of fired carbon and burns smokelessly with intense heat?

Option D

Anthracite, also called hard coal, the most highly metamorphosed form of coal. It contains more fixed carbon (86 percent or greater on a dry, ash-free basis) than any other form of coal and the least amount of volatile matter (14 percent or less on a dry, ash-free basis), and it has calorific values near 35 megajoules per kilogram (approximately 15,000 British thermal units per pound), not much different from the calorific values for most bituminous coal. Anthracite is the least plentiful form of coal. It is found mostly in the eastern part of the United States and makes up less than 2 percent of all coal reserves in the country. Smaller amounts of anthracite occur in South Africa, Australia, western Canada, China, and other countries.