You are presented with the question "What are most buildings heated with?" and the following answer choices: 
- a hydraulic system
 - electromagnetic energy
 - compound of hydrogen oxygen
 - Movement of an air mass
 - cellulose
 - turbine generators
 - lowered energy cost
 - direct energy

Now knowing that electricity sometimes is used for heating buildings and most electricity is created with a turbine generator, choose the best answer.


 

      turbine generators   