You are presented with the question "what can cause burns?" and the following answer choices: 
- epidermis and dermis
 - Pesticides
 - Males and females
 - rays or beams
 - fossil fuels
 - Electrical energy
 - thermal expansion
 - harmful substances

Now knowing that increasing heat causes thermal expansion and thermal burns are caused by exposure to heat, choose the best answer.


 

       thermal expansion  