Final answer:
Coal is a fossil fuel that is primarily composed of carbon. It is formed from the remains of plants and is used as a fuel source in various industries.
Step-by-step explanation:
The resource that is a fossil fuel is coal. Coal is a black or brownish-black sedimentary rock that is primarily composed of carbon, along with various other elements such as hydrogen, sulfur, oxygen, and nitrogen. It is formed from the remains of plants that lived and died millions of years ago. Coal is used as a fuel source in many industries for the generation of electricity and heat.
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