Why is phytoplankton located near the ocean’s surface?
a.
it cannot live in areas of high salinity.
b.
it can more easily evade predators on the oceans’s surface.
c.
it needs access to oxygen only found at the ocean’s surface.
d.
it needs sunlight to survive.

The correct answer is option D, It needs sunlight to survive.

Reason -

Phytoplanktons are the plant species of planktons and thus they need sunlight like all green plants to survive and produce food. The sun light is predominantly available at the ocean’s surface, thus the phytoplanktons occur near the surface of ocean. Along with sunglight , phytoplanktons also need water, nutrients and CO2 to grow which are readily available at the ocean’s surface.