For Metabolic Processes to Occur Within Their Cells, All Living

For metabolic processes to occur within their cells, all living organisms need to maintain homeostasis which means they need

A) to maintain the correct internal temperature, moisture level, and acidity as well as other factors.
B) to rely on the external conditions in the environment to maintain their body temperature.
C) minute to minute and day to day fluctuations in body temperature, moisture level and acidity.
D) to eat other organisms for energy and nutrition.
E) to constantly evolve as the environment changes around them.