The type of organism that is described above would be producers or the plants. They could provide habitat to animals and even to humans. They are the ones who produce oxygen for us to breath by the process of photosynthesis where they take in carbon dioxide from the atmosphere.
I believe you're talking about a population.
Answer:
A
Explanation:
Channel and carrier proteins are both considered facilitated diffusion. We also know that materials do not like to go against the concentration gradient so we can eliminate B.