True or False: The use of biomass fuels includes materials that were once living.

The statement is true because biomass fuels consist of organic materials that were once part of living organisms. This includes a variety of sources such as plant materials, agricultural residues, animal manure, and certain types of waste. These fuels are derived from the biological processes of growth and decomposition, making them renewable energy sources.

By utilizing materials that were once living, biomass fuels help in recycling carbon present in the atmosphere, contributing to a circular carbon economy. This aspect is critical for understanding the potential benefits of using biomass as an energy source, especially in contrast to fossilized materials or synthetic alternatives, which do not originate from contemporary biological processes.