A physiological variable described as "homeostatic" means that it

A、hasvariedfromthenormalvalue,andwillremainconstantatthenewvalue.;
B、nevervariesfromanexactsetpointvalue;
C、isinanequilibriumstatethatrequiresnoenergyinputtostayatthenormalvalue;
D、isinastateofdynamicconstancythatisregulatedtoremainnearastablesetpointvalue;
E、hasnonormalrange,butwilljustchangetomatchtheoutsideenvironmentalconditions