Mammals have a layer of fat under the skin to help insulate the body, and blubber, the fat of the whale, was once much sought after. Given these facts, what insulates among the following options:
- with their fur
 - swamp vegetation
 - copper wire
 - Blankets
 - whale blubber
 - Animal fur
 - steel
 - aluminum foil


 

     whale blubber    