What are the four major ocean basins? are these basins connected?

Arctic, the Atlantic, the Indian, and the Pacific.

These basins are connected.

Explanation:

The ocean basins correspond to the portion of the sea floor that extends from the continental foothills to the mid-oceanic ridge. In these regions occur the abyssal plains, which are extensive areas of relatively flat relief, which occur at depths between 3,000 and 6,000 meters.

The main oceanic basins in the world are connected to each other, they are: the Arctic, the Atlantic, the Indian and the Pacific.