The ocean is one of Earth’s biomes. A biome is an area that is characterized by the plants and animals that live there. There are five major oceans—the Atlantic, Pacific, Indian, Arctic, and Southern—that are all connected in what is known as the World Ocean. The ocean, sometimes called the marine biome, is huge, covering 70% of the Earth’s surface. However, humans have only explored about 5% of it. Scientists know less about the ocean than they do about the dark side of the moon. In this way, the ocean is considered the Earth’s final frontier.

Which of the following is true?

A
The Atlantic, Pacific, Indian, Arctic, and Southern Oceans are completely separate from each other.

B
The ocean covers about half of the Earth’s surface.

C
Scientists have studied most of the ocean, but a tiny bit remains unexplored.

D
Scientists know more about the moon than they do the ocean.