The major biological source of dissolved oxygen in the ocean comes from

There are two sources of dissolve oxygen into water: the atmosphere as well as from the water plants.

Explanation:

There are two sources of dissolve oxygen into water: the atmosphere as well as from the water plants. Phytoplankton or any submerged plants are the main source of oxygen in a pond. These phytoplankton produce oxygen by process  called as photosynthesis in the presence of solar energy and emit this oxygen into the pond

answer(c) carved on a babylonian clay tablet that showed earth as a flat circular disk;

answerformal;