Question

the respiratory system allows for the intake of ____________ in to the body
nitrogen
carbon dioxide
oxygen
hydrogen

Explanation:

The respiratory system's main function is gas - exchange. It takes in oxygen from the air we breathe, which is used by cells for cellular respiration. Nitrogen is a major component of the air but is not directly used in respiration. Carbon dioxide is a waste product of cellular respiration and is exhaled. Hydrogen is not a gas that the respiratory system intakes for normal bodily function.

Answer:

C. Oxygen