Question

Why are phytoplankton commonly referred to as primary producers?

A.
They are decomposers that return nutrients to the ecosystem.

B.
They are autotrophs relied upon directly or indirectly by the rest of the marine biome.

C.
They are heterotrophs that prey on parasites.

D.
They exist in forests where other produce grows.

Answer 1

B.

They are autotrophs relied upon directly or indirectly by the rest of the marine biome

Step-by-step explanation:

Plants make their own food through a process called photosynthesis. Using the energy from the sun, water and carbon dioxide from the atmosphere and nutrients, they chemically make their own food. Since they make or produce their own food they are called producers.