Final answer:
Homeostasis is the term used to describe the maintenance of a stable internal environment necessary for life, which involves the regulation of variables within narrow ranges despite external changes.
Step-by-step explanation:
The maintenance of a stable internal environment compatible for life is called: D. Homeostasis.
Homeostasis is a fundamental property of all living things, referring to the maintenance of a stable internal environment necessary for life. It involves multiple systems within an organism working together to regulate internal functions such as nutrient transport, response to stimuli, and coping with environmental stresses.
In humans, homeostasis entails the regulation of body temperature, pH levels, and essential bodily fluids, ensuring that critical variables like mineral ions and glucose concentrations remain within narrow ranges, despite external environmental changes. This constant adjustment and stability are crucial for the body's overall health and the proper functioning of its organs and organ systems.