Coal.
gas
A seven letter word beginning with C with a the fourth letter C is cracker.
A four letter word beginning with C and ending with X is crux.
carbonate
circuit
Coal is a solid fossil fuel that begins with the letter "c". It is a natural resource formed from the remains of plants and trees that lived millions of years ago. Coal is used for electricity generation and in various industrial processes.
combusting
creamer
choice
childish
cozy
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