Phytoplankton are a diverse group of unicellular organisms that are neither plants nor animals. Phytoplankton use sunlight, carbon dioxide, and nutrients to live and grow. Do you think phytoplankton are producers, consumers, or decomposers? Explain your reasoning.

They are producers

Explanation:

Phytoplankton are producers and this is because they synthesis their own food and produce energy. They photosynthesized and convert carbondioxide and water in the presence of light energy and chlorophyll to carbohydrates and oxygen. They are producers because they produce their own food.