Final answer:
Option (B) Lungs expel waste from the body in the form of carbon dioxide, which is a by-product of the respiratory process and cellular metabolism.
Step-by-step explanation:
Lungs expel waste from the body in the form of carbon dioxide. This expulsion is a part of the respiratory process, where the lungs and the respiratory system work to bring oxygen into the body and release carbon dioxide into the atmosphere.
During respiration, oxygen is transported to body cells for cellular activities, and carbon dioxide, the by-product of these processes, is transported back to the lungs to be expelled. This gas exchange occurs in the alveoli of the lungs, where carbon dioxide moves into the lungs and is then exhaled, completing the process of gas exchange.