Water occupies two main fluid compartments within the body, the intracellular fluid compartment (icf) and the extracellular fluid compartment (ecf). which of the following statements is true concerning the volume of intracellular fluid? oa. all of the water is in the intracellular fluid compartment. b. approximately two-thirds of the water is in the intracellular fluid compartment. c. the intracellular fluid compartment changes greatly, so it is impossible to determine the amountof water at any given time. d. approximately one-third of the water is in the intracellular fluid compartment. e. none of the statements provided are corrected