What is the ultimate non-solar source of geothermal heat? 👤 By The Quiz Wire ✅ Fact Checked 📊 Difficulty Medium 📅 Last Updated 01 Dec 2025 A. Residual formation heat B. Deep-sea pressure C. Radioactive decay of isotopes D. Tectonic friction Check Answer 💡 Explanation: Continuous radioactive decay of elements like uranium and thorium provides the long-term heat source for geothermal energy. 📚 Topics: Environment and Conservation Renewable Energy 🎯 Exams: CSS GEN PMS
