Final answer:
Dead organisms form fossil fuels when buried by sediment.
Step-by-step explanation:
When buried by sediment, dead organisms form fossil fuels. Fossil fuels, such as coal, oil, and natural gas, are formed from the remains of plants and animals that lived millions of years ago. Over time, layers of sediment accumulate and bury these organic materials, subjecting them to high pressure and temperature. This process, known as diagenesis, transforms the organic matter into fossil fuels.
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