Answer:
B.
Step-by-step explanation:
The human body system drawn in the picture is the respiratory system.
The respiratory system is the system of the human body that enables a human to respire or exchange gases with the environment. The respiratory system includes airways, lungs, trachea, nasal cavities, and pharynx.
The primary organ in the respiratory system is the lungs that assist in the exchange of gases.
Therefore, option B is the correct answer.