Correct Answer: Non-conventional energy source

Solution : The correct answer is (B) non-conventional energy source.

Geothermal energy is derived from the heat generated within the Earth's core. It involves harnessing the natural heat energy from the Earth's hot rocks, underground reservoirs of steam or hot water, or shallow ground temperatures. Geothermal energy is considered non-conventional because it utilizes the Earth's internal heat, which is a renewable and sustainable source of energy. Unlike conventional energy sources such as fossil fuels (coal, oil, and natural gas), geothermal energy does not rely on the burning of finite resources and does not produce greenhouse gas emissions. It is a clean and environmentally friendly source of energy.