Which of the following describes fossil fuels?

Fossil fuels are classified as a non-renewable resource because they are created from the remains of ancient plants and animals that have undergone millions of years of geological processes. This process involves heat and pressure, transforming organic material into coal, oil, and natural gas. Once extracted and consumed, these fuels cannot be replenished on a human timescale, meaning they take far longer to form than the period over which they are being used.

In contrast, renewable resources are those that can be replenished naturally in a relatively short time frame, such as solar or wind energy. Sustainable resources refer to those that can be used without depleting their availability for future generations, which does not apply to fossil fuels given their finite nature. Finally, biodegradable resources can break down naturally and return to the ecosystem, a characteristic not applicable to fossil fuels since they are formed from materials that take millions of years to disperse in nature. Thus, the classification of fossil fuels as non-renewable accurately reflects their long formation times and limited availability.