The answer to the question is B - The lungs exhale carbon dioxide, which is a waste gas and needs to be removed from the body.
Both humans and monkeys have this. A VERY long time ago Humans had very small "strings" of skin. This skin has evolved over time and now there is a bone left. Monkeys are technically un-evolved humans. Good thing they stuck around.
Hey there!
I do believe that your answer will be choice A
Parathyriod glands produce a parathyriod hormone aka PTH
The respiratory system brings air into the lungs supplying the blood with oxygen. Oxygen is carried throughout the body to the organs and keeps the heart pumping and when the blood circulates back to the lungs the process starts over again.
