The correct answer is b, antigens
I've looked us up ever since you posted it the only thing I can come up with is letter A because it talks a lot about Mountain chains that talks a lot about the ocean floor and the Hawaiian stuff so try a
Answer:why do you need help? you got this. you're smart.
Explanation:
Answer:
trophic level
Explanation:
Each step of the food chain in the energy pyramid is called a trophic level.
