Without producers, only aquatic ecosystems and their food chains would exist.
What is an ecosystem?
An ecosystem is a geographic area where plants, animals, and other organisms, as well as weather and landscape, work together to form a bubble of life.
The Sun is the major source of energy for organisms and the ecosystems of which they are apart. Producers such as plants, algae, and cyanobacteria use the energy from sunlight to make organic matter from carbon dioxide and water.
In food web, producers are eaten by many different consumers, and most consumers onward are eaten by more than one predator. Most organisms are part of several food chains. A food web starts with the producers in ecosystem and then branches off into interconnected food chains that show who eats whom in ecosystem.
Hence, option B is correct.
Learn more about an ecosystem here:
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