Question

which of the following organism is considered to be the most important organism in an ecosystem? realized species keystone species tertiary consumer

Explanation:

• Realized species is not a term related to the importance of an organism in an ecosystem.
• Keystone species are species that have a disproportionately large effect on their environment relative to their abundance. They play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and numbers of various other species in the community.
• Tertiary consumers are organisms that eat secondary consumers and are high up in the food chain, but they don't have the same fundamental role in maintaining the ecosystem structure as keystone species.

Answer:

B. keystone species