Final answer:
Fossil fuels are formed from the remains of organisms that have undergone anaerobic decomposition over thousands of years.
Step-by-step explanation:
Fossil fuels are created from the remains of organisms that have been preserved in the earth for thousands of years.
Over time, the organic matter of these remains undergoes a process called anaerobic decomposition and converts into fossil fuels such as coal, oil, and natural gas.
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