Answer:
D.
Explanation: Ecology: relation of organisms with one another or their surroundings.
So you can make the world greener
Cells within the body are properly arranged and their production uses up resources of the body. For example, red blood cells use iron while being produced. The body must dispose of cell properly to maintain the orderly arrangement of cells; for example, if dead skin cells were not removed, we would lose feeling in our skin due to the layer of dead cells. Moreover, the body must work to minimize wastage. This is why some of the iron from red blood cells is removed and reused.
They are all part of the Carbon cycle
Explanation:
Photosynthesis is a process during which energy from light is harvested and used to drive synthesis of organic carbohydrates from carbon dioxide and water, generating oxygen. Photosynthesis is the only way that radiant energy from the sun can be converted into organic molecules for plants and animals to consume.