The correct answer for the question is B; Oxygen is used for respiration and carbon dioxide is a waste product.
Explanation;
Plants and animals use the process of respiration to produce energy which is used to fuel normal activities such as growth and movement. The process uses oxygen to break down nutrients such as carbohydrates, fats and proteins, and release energy needed by the plants and animals; but, also creates water and carbon dioxide as byproducts.
Carbon dioxide is a by product of the process of respiration, a chemical reaction that plants and animals use to produce energy they need to carry out day to day activities.
