You are presented with the question "What do humans add to their food?" and the following answer choices: 
- nutrients
 - Proteins
 - Greenhouse gases
 - pain
 - gasoline
 - Heat energy
 - Energy.
 - coal

Now knowing that cooking food requires adding heat energy and many of foods that humans eat are cooked, recooked, and then warmed up, choose the best answer.


 

      Heat energy   