उत्तर : 4. "आर्कटिक"
व्याख्या :

The Arctic Ocean is the smallest of the world's five ocean basins. A polar bear walks on the frozen surface of the Arctic Ocean. The freezing environment provides a home for a diverse range of creatures. With an area of about 6.1 million square miles , the Arctic Ocean is about 1.5 times as big as the United States.