They are among the only types of organisms that get their energy from a non-living thing, and they give energy to Primary consumers, which give energy to secondary consumers, which give energy to tertiary consumers, which can give energy to decomposers, etc.
I think it’s b but idk i’m learning that in science as well
Answer: The Pulmonary vein blood vessel carries oxygenated blood from the lungs back to the heart. Therefore, it carries the highest concentration of oxygen.
Explanation: i think is the answer not sure hope it help this question :)