Answer:B. Respiration
Explanation: During aerobic respiration, oxygen is absorbed by an organism. Respiration occurs all the time in both plants and animals. Respiration is a process by which organic foods usually simple sugars such as glucose are completely broken down enzymatically in living cells in the presence of oxygen to release chemical energy, with the release of carbon dioxide and water as the by-products. The equation for the reaction is C6H12O6 + 6O2 --> 6CO2 + 6H2O + Energy