Which trait enables a polar bear to survive an extremely cold climate

Their thick layers of fur, and high percentage of body fat

Explanations:

Organisms typically have specialized traits, which enable their survival in certain harsh climates. Polar bears are distinctive for their white fur, and fatty layers.

Their fur, which allows them to camouflage in snowy white tundras and swaths of sea ice, is actually made up of two layers; these are soft, shorter dense hairs, along with guard hairs which are longer and thicker. These trap warm air, keeping the bears warm and insulated.Thick layers of body fat called blubber, insulate the bears against gusty cold winds and icy water; temperatures at the arctic average well below freezing. Additionally, the fat keeps them buoyant as they swim, apart from acting as a food store (fat stores energy) when their food source becomes more scarce.

The category is the thing that is most simmilar throughout a period