You are presented with the question "What protects things from freezing in cold weather?" and the following answer choices: 
- exoskeleton
 - thermal insulators
 - thick filling
 - a hydraulic system
 - Animal fur
 - layers of skin
 - layers of fat
 - deep water

Now knowing that athermal insulator slows the transfer of heat and heat transfer fluids, such as antifreeze, protect the solar collector from freezing in cold weather, choose the best answer.


 

  thermal insulators       