Which of these features adapt polar bears to live in cold climate?

The features that help the polar bears to adapt and live in cold climate are:

1. White fur: It helps them to camouflage in the snow and hide from predator. 
2. Fat below skin: The layer of fat insulates the body by maintaining heat in the body.
3. Smell:  Good sense of smell helps them to find food easily in snow or even in the frozen water.