Final answer:
The source of energy that uses organic materials is biomass.
Step-by-step explanation:
The source of energy that uses organic materials is biomass. Biomass refers to any organic matter, such as plants, wood, or agricultural waste, that can be converted into energy. It can be used to produce heat, electricity, and biofuels. For example, wood pellets and agricultural residues like corn stalks can be burned to generate heat, while certain types of bacteria can break down organic material to produce biogas, which can be used as a source of energy.
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