Answer:D. Oxygen is used for respiration and carbon dioxide is a waste product.
Both animal and plant cells use oxygen for respiration, which is the process of converting nutrients into energy. During respiration, oxygen is consumed and carbon dioxide is produced as a waste product. In plant cells, photosynthesis also occurs, which is the process of using sunlight, carbon dioxide, and water to create glucose and oxygen. But respiration, consuming oxygen and producing carbon dioxide, is a common process that happens in both animal and plant cells.
Step-by-step explanation: