The smallest ocean in the world is the Arctic Ocean. It is located in the northern hemisphere and is surrounded by parts of Europe, Asia, and North America. It covers an area of approximately 14.05 million square kilometers, which is about 3.5% of the total area covered by all the oceans on Earth.
The Arctic Ocean is much smaller than the other major oceans, such as the Pacific and the Atlantic, which both cover much larger areas. The Indian Ocean is also larger than the Arctic Ocean. However, despite its relatively small size, the Arctic Ocean is an important body of water that plays a crucial role in regulating the Earth's climate and supporting a unique ecosystem of plants and animals.
Therefore, the correct answer is the Arctic Ocean.