The correct answer is Only C. Key Points • Wood: Wood is a biomass energy source. When burned, wood releases carbon dioxide into the atmosphere, as it contains carbon. This process involves the use of carbon for energy production. Hence, this option involves carbon. • Biogas: Biogas is produced by the anaerobic decomposition of organic matter, such as agricultural waste, manure, and food waste. It primarily consists of methane (CH_(4)) and carbon dioxide (CO_(2)), both of which contain carbon. When biogas is burned for energy, it releases carbon dioxide into the atmosphere. Hence, this option also involves carbon. • Geothermal Energy: Geothermal energy is derived from the heat stored within the Earth. This energy source does not involve any carbon-based fuels or the release of carbon dioxide during the production process. It is a clean and sustainable energy source. Hence, this option does not involve carbon. • Coal: Coal is a fossil fuel that contains a high percentage of carbon. When burned, it releases carbon dioxide into the atmosphere, contributing to greenhouse gas emissions. Hence, this option involves carbon. • Correct Answer: The only option that does not involve the use of carbon in any form for energy production is Geothermal Energy (C). Additional Information • Wood: • Wood is a traditional source of energy and is commonly used for cooking and heating in rural areas. • It is considered renewable but emits carbon dioxide during combustion. • In modern times, wood is also used in biomass power plants to generate electricity. • Biogas: • Biogas is a renewable energy source produced from organic waste through anaerobic digestion. • It is widely used in rural areas for cooking and lighting. • Despite being renewable, it emits carbon dioxide when burned, but the net emissions are lower compared to fossil fuels. • Geothermal Energy: • Geothermal energy is harnessed from the heat stored in the Earth's crust. • It is used for generating electricity and direct heating applications. • Geothermal energy is highly sustainable, reliable, and environmentally friendly, as it does not emit carbon dioxide during its utilization. • Countries like Iceland, the United States, the Philippines, and Indonesia are leading producers of geothermal energy. • Coal: • Coal is a non-renewable fossil fuel widely used for generating electricity and industrial applications. • It is one of the major contributors to greenhouse gas emissions due to its high carbon content. • Coal-based power plants are a significant source of air pollution and climate change. Important Points • Carbon and Energy Production: • Carbon-based fuels include coal, petroleum, natural gas, wood, and biogas. • Burning these fuels releases carbon dioxide, which contributes to global warming and air pollution. • Transitioning to non-carbon-based energy sources, such as geothermal, solar, wind, and hydro, is crucial for mitigating climate change. • Geothermal Energy Statistics: • Globally, geothermal energy accounts for approximately 0.3% of electricity generation. • The United States is the largest producer of geothermal electricity, followed by Indonesia and the Philippines. • Geothermal plants operate with a capacity factor of around 90%, making them highly reliable compared to other renewable energy sources.