A fuel derived from a biological source is known as a:

A fuel derived from a biological source is identified as biofuel. Biofuels are produced from organic materials, which can include plant crops, agricultural residues, and animal waste. They are considered renewable energy sources, as they can be replenished over time through the growth of new biomass.

Biofuels are significant in the context of reducing greenhouse gas emissions compared to traditional fossil fuels because their production and combustion tend to have a smaller carbon footprint. This is due to the fact that the CO2 released during their combustion can be offset by the CO2 absorbed by the plants during their growth cycle.

The other options represent different types of fuel sources. Fossil fuel refers specifically to energy sources formed from ancient organic matter buried beneath layers of the earth, such as coal, oil, and natural gas. Hydrocarbon is a broad term that includes a variety of organic compounds made solely of hydrogen and carbon, which can be found in both fossil fuels and biofuels. Natural gas is a specific type of fossil fuel primarily composed of methane, formed from the decomposition of organic matter over millions of years.