Some people prefer interval training because
a. the intensity of the exercise doesn't increase, only the time does. b. they can exercise at a steady, but slow, pace for longer periods of time. c. it's performed with speed and may not cause boredom. d. they've found that this type of training is best for beginners

answer; i believe the correct answer is (secondary prevention);

fluid balance is an aspect of the homeostasis of organisms in which the amount of water in the organism needs to be controlled, via osmoregulation and behavior, such that the concentrations of electrolytes (salts in solution) in the various body fluids are kept within healthy ranges. the core principle of fluid balance is that the amount of water lost from the body must equal the amount of water taken in.