In addition to its main function, the digestive system also
a. the body maintain fluids
b. the body regulate immune responses
c. both a and b
d. neither a nor b

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.

true. these things define the personality of the person.