Which of the following can be inferred from paragraphs 2 and 3 about geothermal reservoirs? A. Volcanic heat is associated only with geothermal reservoirs that have a temperature over 180℃. B. More countries produce power from geothermal reservoirs than use them for heating buildings. C. Most geothermal reservoirs are suitable for producing electricity. D. A higher geothermal reservoir temperature is needed to generate electricity than is needed to heat homes.