Answer:
You either are referring to the fish Chordate, or the animal classification. In the case of the classification it is literally any animal that has developed any sort of dorsal fin, for example some snakes can fall under this classification.
I think is D Carbon dioxide
PLEASE MARK ME AS BRAINLIEST
Each organ of the body produces pangenes which travel through the blood to the reproduction organs to be given to offspring. This is of course false as proven by scientists.
I would say D...just because of the greenhouse effect