Energy is used for heating a building by a heating system, and geothermal energy is used for heating and cooling systems. Given these facts, what is a way to heat a building among the following options:
- sound
 - Movement of an air mass
 - burning coal
 - static electricity
 - In the winter
 - potential energy
 - by indirect light
 - geothermal energy


 

        geothermal energy 