Carbon Lumps Used as Barbecue Fuel
Puzzle 8 of Jokes and Gags Medium Pack
Question is: Carbon Lumps Used as Barbecue Fuel
and the answer is: CHARCOAL
Word Meaning:
CHARCOAL — (countable, uncountable) impure carbon obtained by destructive distillation of wood or other organic matter, that is, heating it in the absence of oxygen.
Definitions from Wiktionary.