Answer:
The correct answer is: homeostasis.
Step-by-step explanation:
Homeostasis is the state in which an organism maintains its internal conditions so it can function properly. If homeostasis fails, diseases appear.
In order to maintain homeostasis, there are many conditions that are regulated regularly, from body temperature to pH, and fluid balance. For homeostasis to be maintained, different systems participate in the regulation of these conditions.
The example provided in the question is a process performed by many structures in different organs that help regulate the concentration of fluids.