Final answer:
Homeostasis is the process of maintaining a stable internal environment in the body through continuous adjustments and feedback mechanisms, to ensure physiological variables remain within certain ranges. Option c.
Step-by-step explanation:
Homeostasis best describes (c) a relatively constant environment within the body. It is the process by which the human body maintains a stable internal condition despite changes in external conditions. Homeostasis involves continuous monitoring and constant adjustments made by the cells, tissues, organs, and organ systems to ensure that various physiological variables remain within certain ranges and to achieve equilibrium. A key element in maintaining homeostasis is the feedback mechanism, which includes a stimulus, a receptor, and a response. For instance, the regulation of body temperature and glucose levels are both examples of the body striving to maintain homeostatic balance. If the body becomes too warm, mechanisms are triggered to cool it down. Similarly, if glucose levels rise, the body responds to lower them to maintain a set point, which is the ideal value for a physiological condition.