Definition: this is the ocean found on the east coast of the united states and the west coast of some european and african countries.

The ocean that matches this definition: is the ocean found on the east coast of the united states and the west coast of some european and african countries. Is:

The Atlantic Ocean

Explanation:

The Atlantic ocean comprehends the water mass between the east European coast, and the western North American coast in the northern hemisphere. The African east coast and the South American west coast in the southern hemisphere. It is known to be the richest of them due to late exploration and exploitation.

the answer is option a.