I'm sure the answer is diffusion
Chloroplast converts energy from the sun into sugars the cells of the plant can use. this process is referred to as photosynthesis
The amount of hyaline cartilage in the embryonic skeleton is much higher than in a child. This is because the embryonic skeleton will still go calcification as the embryo ages to fetus and eventually to being a child to adulthood.
There is no answer ,you wrote the answers with the question
The best answer is D, birds.
For more information and details on the way a bird's respiratory system works:
https://asknature.org/strategy/air-flow-patterns-facilitate-efficient-gas-exchange/
