Which renewable energy source involves combustion of organic materials?

Biomass energy is derived from the combustion of organic materials, which can include plant matter, agricultural residues, and other biological materials. When these organic materials are burned, they release stored energy in the form of heat, which can be utilized for various purposes, such as generating electricity or heating. This process not only provides a renewable source of energy but can also help reduce waste by converting materials that would otherwise be discarded into usable fuel.

The other energy sources listed do not involve combustion of organic materials. Hydroelectric energy harnesses the power of flowing water, geothermal energy utilizes heat from the Earth’s interior, and solar energy captures sunlight. Each of these methods utilizes different natural phenomena and does not rely on burning organic matter for energy production.