D!! is the correct answer bro good luck!
They use there fins to propel themselves
hope this was useful to you
Answer:
They help our ecosystems and food chains all over the world
Explanation:
Autotrophs are the most important organisms on the planet because they are fundamental to food chains all over the world. They take energy from the environment in the form of sunlight or inorganic chemicals and use it to create fuel molecules like carbohydrates to release the hydrogen atoms that fuel the metabolic process of primary production.
<em>Explanation is in the paragraph above. Hope that helps!</em>