Which are the most common producers in aquatic ecosystems?
a - bacteria
b -algae
c -fish
d -plants

b -algae

Explanation:

The most common producers in aquatic ecosystems are the algae. They are called phytoplanktons.

In the food web and food chain of aquatic ecosystems, they usually set out with the algae. These algae are called phytoplanktons. They are the producers in all aquatic ecosystem. Phytoplanktons consists of algae and cyanobacteria. Just like plants on land, phytoplanktons manufacture food in an aquatic ecosystem.