Final answer:
Seagross, Sea Urchin, and Orca are considered heterotrophs.
Step-by-step explanation:
Heterotrophs are organisms that cannot produce their own food and rely on consuming other organisms to obtain energy. Out of the given options, Seagross, Sea Urchin, and Orca are considered heterotrophs as they obtain nutrients by consuming other organisms.
Learn more about Heterotrophs