The immune system helps neutralize disease and infection. The digestive system processes nutrients from food. The skeletal system includes your bones and supports and protects your body. The correct answer is the nervous system.
Answer:
The polar bear is an animal which is prevalent in the arctic region of the world which is characterized by very cold icy climate.
They adapt to these climatic conditions by maintaining a body temperature of 37°C through its thick fur and tough skin. It also has an insulating fat layer (adipose tissues) which is very thick.
This insulation helps in keeping the animal very warm in extreme temperatures.
